MasterObserver (Apache HBase 2.3.0 API)

All Known Implementing Classes:

AccessController, CoprocessorWhitelistMasterObserver, ExampleMasterObserverWithMetrics, MasterQuotasObserver, RSGroupAdminEndpoint, SnapshotScannerHDFSAclController, VisibilityController
```
@InterfaceAudience.LimitedPrivate(value="Coprocesssor")
 @InterfaceStability.Evolving
public interface MasterObserver
```
Defines coprocessor hooks for interacting with operations on the HMaster process.

Since most implementations will be interested in only a subset of hooks, this class uses 'default' functions to avoid having to add unnecessary overrides. When the functions are non-empty, it's simply to satisfy the compiler by returning value of expected (non-void) type. It is done in a way that these default definitions act as no-op. So our suggestion to implementation would be to not call these 'default' methods from overrides.

Exception Handling
For all functions, exception handling is done as follows:
- Exceptions of type IOException are reported back to client.
- For any other kind of exception:
  - If the configuration CoprocessorHost.ABORT_ON_ERROR_KEY is set to true, then the server aborts.
  - Otherwise, coprocessor is removed from the server and DoNotRetryIOException is returned to the client.

Method Summary

All Methods Instance Methods Default Methods Deprecated Methods
Modifier and Type	Method and Description
`default void`	`postAbortProcedure(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called after a abortProcedure request has been processed.
`default void`	`postAddReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId, ReplicationPeerConfig peerConfig)` Called after add a replication peer
`default void`	`postAddRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx, String name)` Called after a new region server group is added
`default void`	`postAssign(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo regionInfo)` Called after the region assignment has been requested.
`default void`	`postBalance(ObserverContext<MasterCoprocessorEnvironment> ctx, List<RegionPlan> plans)` Called after the balancing plan has been submitted.
`default void`	`postBalanceRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx, String groupName, boolean balancerRan)` Called after a region server group is removed
`default void`	`postBalanceSwitch(ObserverContext<MasterCoprocessorEnvironment> ctx, boolean oldValue, boolean newValue)` Called after the flag to enable/disable balancing has changed.
`default void`	`postClearDeadServers(ObserverContext<MasterCoprocessorEnvironment> ctx, List<ServerName> servers, List<ServerName> notClearedServers)` Called after clear dead region servers.
`default void`	`postCloneSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot, TableDescriptor tableDescriptor)` Called after a snapshot clone operation has been requested.
`default void`	`postCompletedCreateTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableDescriptor desc, RegionInfo[] regions)` Called after the createTable operation has been requested.
`default void`	`postCompletedDeleteTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called after `HMaster` deletes a table.
`default void`	`postCompletedDisableTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called after the disableTable operation has been requested.
`default void`	`postCompletedEnableTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called after the enableTable operation has been requested.
`default void`	`postCompletedMergeRegionsAction(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo[] regionsToMerge, RegionInfo mergedRegion)` called after the regions merge.
`default void`	`postCompletedModifyTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, TableDescriptor currentDescriptor)` Deprecated. Since 2.1. Will be removed in 3.0.
`default void`	`postCompletedModifyTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, TableDescriptor oldDescriptor, TableDescriptor currentDescriptor)` Called after to modifying a table's properties.
`default void`	`postCompletedSnapshotAction(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot, TableDescriptor tableDescriptor)` Called after the snapshot operation has been completed.
`default void`	`postCompletedSplitRegionAction(ObserverContext<MasterCoprocessorEnvironment> c, RegionInfo regionInfoA, RegionInfo regionInfoB)` Called after the region is split.
`default void`	`postCompletedTruncateTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called after `HMaster` truncates a table.
`default void`	`postCreateNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx, NamespaceDescriptor ns)` Called after the createNamespace operation has been requested.
`default void`	`postCreateTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableDescriptor desc, RegionInfo[] regions)` Called after the createTable operation has been requested.
`default void`	`postDecommissionRegionServers(ObserverContext<MasterCoprocessorEnvironment> ctx, List<ServerName> servers, boolean offload)` Called after decommission region servers.
`default void`	`postDeleteNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx, String namespace)` Called after the deleteNamespace operation has been requested.
`default void`	`postDeleteSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot)` Called after the delete snapshot operation has been requested.
`default void`	`postDeleteTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called after the deleteTable operation has been requested.
`default void`	`postDisableReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId)` Called after disable a replication peer
`default void`	`postDisableTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called after the disableTable operation has been requested.
`default void`	`postEnableReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId)` Called after enable a replication peer
`default void`	`postEnableTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called after the enableTable operation has been requested.
`default void`	`postGetClusterMetrics(ObserverContext<MasterCoprocessorEnvironment> ctx, ClusterMetrics status)` Called after get cluster status.
`default void`	`postGetLocks(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called after a getLocks request has been processed.
`default void`	`postGetNamespaceDescriptor(ObserverContext<MasterCoprocessorEnvironment> ctx, NamespaceDescriptor ns)` Called after a getNamespaceDescriptor request has been processed.
`default void`	`postGetProcedures(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called after a getProcedures request has been processed.
`default void`	`postGetReplicationPeerConfig(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId)` Called after get the configured ReplicationPeerConfig for the specified peer
`default void`	`postGetTableDescriptors(ObserverContext<MasterCoprocessorEnvironment> ctx, List<TableName> tableNamesList, List<TableDescriptor> descriptors, String regex)` Called after a getTableDescriptors request has been processed.
`default void`	`postGetTableNames(ObserverContext<MasterCoprocessorEnvironment> ctx, List<TableDescriptor> descriptors, String regex)` Called after a getTableNames request has been processed.
`default void`	`postGetUserPermissions(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, String namespace, TableName tableName, byte[] family, byte[] qualifier)` Called after getting user permissions.
`default void`	`postGrant(ObserverContext<MasterCoprocessorEnvironment> ctx, UserPermission userPermission, boolean mergeExistingPermissions)` Called after granting user permissions.
`default void`	`postHasUserPermissions(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, List<Permission> permissions)` Called after checking if user has permissions.
`default void`	`postIsRpcThrottleEnabled(ObserverContext<MasterCoprocessorEnvironment> ctx, boolean rpcThrottleEnabled)` Called after getting if is rpc throttle enabled.
`default void`	`postListDecommissionedRegionServers(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called after list decommissioned region servers.
`default void`	`postListNamespaceDescriptors(ObserverContext<MasterCoprocessorEnvironment> ctx, List<NamespaceDescriptor> descriptors)` Called after a listNamespaceDescriptors request has been processed.
`default void`	`postListNamespaces(ObserverContext<MasterCoprocessorEnvironment> ctx, List<String> namespaces)` Called after a listNamespaces request has been processed.
`default void`	`postListReplicationPeers(ObserverContext<MasterCoprocessorEnvironment> ctx, String regex)` Called after list replication peers.
`default void`	`postListSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot)` Called after listSnapshots request has been processed.
`default void`	`postLockHeartbeat(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called after heartbeat to a lock.
`default void`	`postMergeRegions(ObserverContext<MasterCoprocessorEnvironment> c, RegionInfo[] regionsToMerge)` called after merge regions request.
`default void`	`postMergeRegionsCommitAction(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo[] regionsToMerge, RegionInfo mergedRegion)` This will be called after META step as part of regions merge transaction.
`default void`	`postModifyNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx, NamespaceDescriptor currentNsDescriptor)` Deprecated. Since 2.1. Will be removed in 3.0.
`default void`	`postModifyNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx, NamespaceDescriptor oldNsDescriptor, NamespaceDescriptor currentNsDescriptor)` Called after the modifyNamespace operation has been requested.
`default void`	`postModifyTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, TableDescriptor currentDescriptor)` Deprecated. Since 2.1. Will be removed in 3.0.
`default void`	`postModifyTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, TableDescriptor oldDescriptor, TableDescriptor currentDescriptor)` Called after the modifyTable operation has been requested.
`default void`	`postMove(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo region, ServerName srcServer, ServerName destServer)` Called after the region move has been requested.
`default void`	`postMoveServers(ObserverContext<MasterCoprocessorEnvironment> ctx, Set<Address> servers, String targetGroup)` Called after servers are moved to target region server group
`default void`	`postMoveServersAndTables(ObserverContext<MasterCoprocessorEnvironment> ctx, Set<Address> servers, Set<TableName> tables, String targetGroup)` Called after servers are moved to target region server group
`default void`	`postMoveTables(ObserverContext<MasterCoprocessorEnvironment> ctx, Set<TableName> tables, String targetGroup)` Called after servers are moved to target region server group
`default void`	`postRecommissionRegionServer(ObserverContext<MasterCoprocessorEnvironment> ctx, ServerName server, List<byte[]> encodedRegionNames)` Called after recommission region server.
`default void`	`postRegionOffline(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo regionInfo)` Called after the region has been marked offline.
`default void`	`postRemoveReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId)` Called after remove a replication peer
`default void`	`postRemoveRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx, String name)` Called after a region server group is removed
`default void`	`postRemoveServers(ObserverContext<MasterCoprocessorEnvironment> ctx, Set<Address> servers)` Called after servers are removed from rsgroup
`default void`	`postRenameRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx, String oldName, String newName)` Called after rename rsgroup.
`default void`	`postRequestLock(ObserverContext<MasterCoprocessorEnvironment> ctx, String namespace, TableName tableName, RegionInfo[] regionInfos, String description)` Called after new LockProcedure is queued.
`default void`	`postRestoreSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot, TableDescriptor tableDescriptor)` Called after a snapshot restore operation has been requested.
`default void`	`postRevoke(ObserverContext<MasterCoprocessorEnvironment> ctx, UserPermission userPermission)` Called after revoking user permissions.
`default void`	`postRollBackMergeRegionsAction(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo[] regionsToMerge)` This will be called after the roll back of the regions merge.
`default void`	`postRollBackSplitRegionAction(ObserverContext<MasterCoprocessorEnvironment> ctx)` This will be called after the roll back of the split region is completed
`default void`	`postSetNamespaceQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String namespace, GlobalQuotaSettings quotas)` Called after the quota for the namespace is stored.
`default void`	`postSetRegionServerQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String regionServer, GlobalQuotaSettings quotas)` Called after the quota for the region server is stored.
`default void`	`postSetSplitOrMergeEnabled(ObserverContext<MasterCoprocessorEnvironment> ctx, boolean newValue, MasterSwitchType switchType)` Called after setting split / merge switch
`default void`	`postSetTableQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, GlobalQuotaSettings quotas)` Called after the quota for the table is stored.
`default void`	`postSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, GlobalQuotaSettings quotas)` Called after the quota for the user is stored.
`default void`	`postSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, String namespace, GlobalQuotaSettings quotas)` Called after the quota for the user on the specified namespace is stored.
`default void`	`postSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, TableName tableName, GlobalQuotaSettings quotas)` Called after the quota for the user on the specified table is stored.
`default void`	`postSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot, TableDescriptor tableDescriptor)` Called after the snapshot operation has been requested.
`default void`	`postStartMaster(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called immediately after an active master instance has completed initialization.
`default void`	`postSwitchExceedThrottleQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, boolean oldValue, boolean newValue)` Called after switching exceed throttle quota state.
`default void`	`postSwitchRpcThrottle(ObserverContext<MasterCoprocessorEnvironment> ctx, boolean oldValue, boolean newValue)` Called after switching rpc throttle enabled state.
`default void`	`postTableFlush(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called after the table memstore is flushed to disk.
`default void`	`postTruncateTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called after the truncateTable operation has been requested.
`default void`	`postUnassign(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo regionInfo, boolean force)` Called after the region unassignment has been requested.
`default void`	`postUpdateReplicationPeerConfig(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId, ReplicationPeerConfig peerConfig)` Called after update peerConfig for the specified peer
`default void`	`preAbortProcedure(ObserverContext<MasterCoprocessorEnvironment> ctx, long procId)` Called before a abortProcedure request has been processed.
`default void`	`preAddReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId, ReplicationPeerConfig peerConfig)` Called before add a replication peer
`default void`	`preAddRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx, String name)` Called before a new region server group is added
`default void`	`preAssign(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo regionInfo)` Called prior to assigning a specific region.
`default void`	`preBalance(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called prior to requesting rebalancing of the cluster regions, though after the initial checks for regions in transition and the balance switch flag.
`default void`	`preBalanceRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx, String groupName)` Called before a region server group is removed
`default void`	`preBalanceSwitch(ObserverContext<MasterCoprocessorEnvironment> ctx, boolean newValue)` Called prior to modifying the flag used to enable/disable region balancing.
`default void`	`preClearDeadServers(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called before clear dead region servers.
`default void`	`preCloneSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot, TableDescriptor tableDescriptor)` Called before a snapshot is cloned.
`default void`	`preCreateNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx, NamespaceDescriptor ns)` Called before a new namespace is created by `HMaster`.
`default void`	`preCreateTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableDescriptor desc, RegionInfo[] regions)` Called before a new table is created by `HMaster`.
`default void`	`preCreateTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableDescriptor desc, RegionInfo[] regions)` Called before a new table is created by `HMaster`.
`default TableDescriptor`	`preCreateTableRegionsInfos(ObserverContext<MasterCoprocessorEnvironment> ctx, TableDescriptor desc)` Called before we create the region infos for this table.
`default void`	`preDecommissionRegionServers(ObserverContext<MasterCoprocessorEnvironment> ctx, List<ServerName> servers, boolean offload)` Called before decommission region servers.
`default void`	`preDeleteNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx, String namespace)` Called before `HMaster` deletes a namespace
`default void`	`preDeleteSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot)` Called before a snapshot is deleted.
`default void`	`preDeleteTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called before `HMaster` deletes a table.
`default void`	`preDeleteTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called before `HMaster` deletes a table.
`default void`	`preDisableReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId)` Called before disable a replication peer
`default void`	`preDisableTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called prior to disabling a table.
`default void`	`preDisableTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called prior to disabling a table.
`default void`	`preEnableReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId)` Called before enable a replication peer
`default void`	`preEnableTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called prior to enabling a table.
`default void`	`preEnableTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called prior to enabling a table.
`default void`	`preGetClusterMetrics(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called before get cluster status.
`default void`	`preGetLocks(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called before a getLocks request has been processed.
`default void`	`preGetNamespaceDescriptor(ObserverContext<MasterCoprocessorEnvironment> ctx, String namespace)` Called before a getNamespaceDescriptor request has been processed.
`default void`	`preGetProcedures(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called before a getProcedures request has been processed.
`default void`	`preGetReplicationPeerConfig(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId)` Called before get the configured ReplicationPeerConfig for the specified peer
`default void`	`preGetTableDescriptors(ObserverContext<MasterCoprocessorEnvironment> ctx, List<TableName> tableNamesList, List<TableDescriptor> descriptors, String regex)` Called before a getTableDescriptors request has been processed.
`default void`	`preGetTableNames(ObserverContext<MasterCoprocessorEnvironment> ctx, List<TableDescriptor> descriptors, String regex)` Called before a getTableNames request has been processed.
`default void`	`preGetUserPermissions(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, String namespace, TableName tableName, byte[] family, byte[] qualifier)` Called before getting user permissions.
`default void`	`preGrant(ObserverContext<MasterCoprocessorEnvironment> ctx, UserPermission userPermission, boolean mergeExistingPermissions)` Called before granting user permissions.
`default void`	`preHasUserPermissions(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, List<Permission> permissions)`
`default void`	`preIsRpcThrottleEnabled(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called before getting if is rpc throttle enabled.
`default void`	`preListDecommissionedRegionServers(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called before list decommissioned region servers.
`default void`	`preListNamespaceDescriptors(ObserverContext<MasterCoprocessorEnvironment> ctx, List<NamespaceDescriptor> descriptors)` Called before a listNamespaceDescriptors request has been processed.
`default void`	`preListNamespaces(ObserverContext<MasterCoprocessorEnvironment> ctx, List<String> namespaces)` Called before a listNamespaces request has been processed.
`default void`	`preListReplicationPeers(ObserverContext<MasterCoprocessorEnvironment> ctx, String regex)` Called before list replication peers.
`default void`	`preListSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot)` Called before listSnapshots request has been processed.
`default void`	`preLockHeartbeat(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tn, String description)` Called before heartbeat to a lock.
`default void`	`preMasterInitialization(ObserverContext<MasterCoprocessorEnvironment> ctx)` Call before the master initialization is set to true.
`default void`	`preMergeRegions(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo[] regionsToMerge)` Called before merge regions request.
`default void`	`preMergeRegionsAction(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo[] regionsToMerge)` Called before the regions merge.
`default void`	`preMergeRegionsCommitAction(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo[] regionsToMerge, List<Mutation> metaEntries)` This will be called before update META step as part of regions merge transaction.
`default void`	`preModifyNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx, NamespaceDescriptor newNsDescriptor)` Deprecated. Since 2.1. Will be removed in 3.0.
`default void`	`preModifyNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx, NamespaceDescriptor currentNsDescriptor, NamespaceDescriptor newNsDescriptor)` Called prior to modifying a namespace's properties.
`default void`	`preModifyTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, TableDescriptor newDescriptor)` Deprecated. Since 2.1. Will be removed in 3.0.
`default TableDescriptor`	`preModifyTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, TableDescriptor currentDescriptor, TableDescriptor newDescriptor)` Called prior to modifying a table's properties.
`default void`	`preModifyTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, TableDescriptor newDescriptor)` Deprecated. Since 2.1. Will be removed in 3.0.
`default void`	`preModifyTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, TableDescriptor currentDescriptor, TableDescriptor newDescriptor)` Called prior to modifying a table's properties.
`default void`	`preMove(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo region, ServerName srcServer, ServerName destServer)` Called prior to moving a given region from one region server to another.
`default void`	`preMoveServers(ObserverContext<MasterCoprocessorEnvironment> ctx, Set<Address> servers, String targetGroup)` Called before servers are moved to target region server group
`default void`	`preMoveServersAndTables(ObserverContext<MasterCoprocessorEnvironment> ctx, Set<Address> servers, Set<TableName> tables, String targetGroup)` Called before servers are moved to target region server group
`default void`	`preMoveTables(ObserverContext<MasterCoprocessorEnvironment> ctx, Set<TableName> tables, String targetGroup)` Called before tables are moved to target region server group
`default void`	`preRecommissionRegionServer(ObserverContext<MasterCoprocessorEnvironment> ctx, ServerName server, List<byte[]> encodedRegionNames)` Called before recommission region server.
`default void`	`preRegionOffline(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo regionInfo)` Called prior to marking a given region as offline.
`default void`	`preRemoveReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId)` Called before remove a replication peer
`default void`	`preRemoveRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx, String name)` Called before a region server group is removed
`default void`	`preRemoveServers(ObserverContext<MasterCoprocessorEnvironment> ctx, Set<Address> servers)` Called before servers are removed from rsgroup
`default void`	`preRenameRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx, String oldName, String newName)` Called before rename rsgroup.
`default void`	`preRequestLock(ObserverContext<MasterCoprocessorEnvironment> ctx, String namespace, TableName tableName, RegionInfo[] regionInfos, String description)` Called before new LockProcedure is queued.
`default void`	`preRestoreSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot, TableDescriptor tableDescriptor)` Called before a snapshot is restored.
`default void`	`preRevoke(ObserverContext<MasterCoprocessorEnvironment> ctx, UserPermission userPermission)` Called before revoking user permissions.
`default void`	`preSetNamespaceQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String namespace, GlobalQuotaSettings quotas)` Called before the quota for the namespace is stored.
`default void`	`preSetRegionServerQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String regionServer, GlobalQuotaSettings quotas)` Called before the quota for the region server is stored.
`default void`	`preSetSplitOrMergeEnabled(ObserverContext<MasterCoprocessorEnvironment> ctx, boolean newValue, MasterSwitchType switchType)` Called prior to setting split / merge switch Supports Coprocessor 'bypass'.
`default void`	`preSetTableQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName, GlobalQuotaSettings quotas)` Called before the quota for the table is stored.
`default void`	`preSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, GlobalQuotaSettings quotas)` Called before the quota for the user is stored.
`default void`	`preSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, String namespace, GlobalQuotaSettings quotas)` Called before the quota for the user on the specified namespace is stored.
`default void`	`preSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, String userName, TableName tableName, GlobalQuotaSettings quotas)` Called before the quota for the user on the specified table is stored.
`default void`	`preShutdown(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called prior to shutting down the full HBase cluster, including this `HMaster` process.
`default void`	`preSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx, SnapshotDescription snapshot, TableDescriptor tableDescriptor)` Called before a new snapshot is taken.
`default void`	`preSplitRegion(ObserverContext<MasterCoprocessorEnvironment> c, TableName tableName, byte[] splitRow)` Called before the split region procedure is called.
`default void`	`preSplitRegionAction(ObserverContext<MasterCoprocessorEnvironment> c, TableName tableName, byte[] splitRow)` Called before the region is split.
`default void`	`preSplitRegionAfterMETAAction(ObserverContext<MasterCoprocessorEnvironment> ctx)` This will be called after update META step as part of split transaction
`default void`	`preSplitRegionBeforeMETAAction(ObserverContext<MasterCoprocessorEnvironment> ctx, byte[] splitKey, List<Mutation> metaEntries)` This will be called before update META step as part of split transaction.
`default void`	`preStopMaster(ObserverContext<MasterCoprocessorEnvironment> ctx)` Called immediately prior to stopping this `HMaster` process.
`default void`	`preSwitchExceedThrottleQuota(ObserverContext<MasterCoprocessorEnvironment> ctx, boolean enable)` Called before switching exceed throttle quota state.
`default void`	`preSwitchRpcThrottle(ObserverContext<MasterCoprocessorEnvironment> ctx, boolean enable)` Called before switching rpc throttle enabled state.
`default void`	`preTableFlush(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called before the table memstore is flushed to disk.
`default void`	`preTruncateTable(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called before `HMaster` truncates a table.
`default void`	`preTruncateTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx, TableName tableName)` Called before `HMaster` truncates a table.
`default void`	`preUnassign(ObserverContext<MasterCoprocessorEnvironment> ctx, RegionInfo regionInfo, boolean force)` Called prior to unassigning a given region.
`default void`	`preUpdateReplicationPeerConfig(ObserverContext<MasterCoprocessorEnvironment> ctx, String peerId, ReplicationPeerConfig peerConfig)` Called before update peerConfig for the specified peer

Method Detail

preCreateTableRegionsInfos
```
default TableDescriptor preCreateTableRegionsInfos(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                                   TableDescriptor desc)
                                            throws IOException
```
Called before we create the region infos for this table. Called as part of create table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

desc - the TableDescriptor for the table

Returns:

the TableDescriptor used to create the table. Default is the one passed in. Return null means cancel the creation.

Throws:

IOException

preCreateTable

default void preCreateTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                            TableDescriptor desc,
                            RegionInfo[] regions)
                     throws IOException

Called before a new table is created by HMaster. Called as part of create table RPC call.

Parameters:: ctx - the environment to interact with the framework and master; desc - the TableDescriptor for the table; regions - the initial regions created for the table
Throws:: IOException

postCreateTable
```
default void postCreateTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             TableDescriptor desc,
                             RegionInfo[] regions)
                      throws IOException
```
Called after the createTable operation has been requested. Called as part of create table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

desc - the TableDescriptor for the table

regions - the initial regions created for the table

Throws:

IOException

preCreateTableAction
```
default void preCreateTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                  TableDescriptor desc,
                                  RegionInfo[] regions)
                           throws IOException
```
Called before a new table is created by HMaster. Called as part of create table procedure and it is async to the create RPC call.

Parameters:

ctx - the environment to interact with the framework and master

desc - the TableDescriptor for the table

regions - the initial regions created for the table

Throws:

IOException

postCompletedCreateTableAction
```
default void postCompletedCreateTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                            TableDescriptor desc,
                                            RegionInfo[] regions)
                                     throws IOException
```
Called after the createTable operation has been requested. Called as part of create table RPC call. Called as part of create table procedure and it is async to the create RPC call.

Parameters:

ctx - the environment to interact with the framework and master

desc - the TableDescriptor for the table

regions - the initial regions created for the table

Throws:

IOException

preDeleteTable
```
default void preDeleteTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                            TableName tableName)
                     throws IOException
```
Called before HMaster deletes a table. Called as part of delete table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

postDeleteTable
```
default void postDeleteTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             TableName tableName)
                      throws IOException
```
Called after the deleteTable operation has been requested. Called as part of delete table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

preDeleteTableAction
```
default void preDeleteTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                  TableName tableName)
                           throws IOException
```
Called before HMaster deletes a table. Called as part of delete table procedure and it is async to the delete RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

postCompletedDeleteTableAction
```
default void postCompletedDeleteTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                            TableName tableName)
                                     throws IOException
```
Called after HMaster deletes a table. Called as part of delete table procedure and it is async to the delete RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

preTruncateTable
```
default void preTruncateTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              TableName tableName)
                       throws IOException
```
Called before HMaster truncates a table. Called as part of truncate table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

postTruncateTable
```
default void postTruncateTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               TableName tableName)
                        throws IOException
```
Called after the truncateTable operation has been requested. Called as part of truncate table RPC call. The truncate is synchronous, so this method will be called when the truncate operation is terminated.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

preTruncateTableAction
```
default void preTruncateTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                    TableName tableName)
                             throws IOException
```
Called before HMaster truncates a table. Called as part of truncate table procedure and it is async to the truncate RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

postCompletedTruncateTableAction
```
default void postCompletedTruncateTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                              TableName tableName)
                                       throws IOException
```
Called after HMaster truncates a table. Called as part of truncate table procedure and it is async to the truncate RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

preModifyTable

@Deprecated
default void preModifyTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                        TableName tableName,
                                        TableDescriptor newDescriptor)
                                 throws IOException

Deprecated. Since 2.1. Will be removed in 3.0.

Called prior to modifying a table's properties. Called as part of modify table RPC call.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; newDescriptor - after modify operation, table will have this descriptor
Throws:: IOException

preModifyTable

default TableDescriptor preModifyTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                       TableName tableName,
                                       TableDescriptor currentDescriptor,
                                       TableDescriptor newDescriptor)
                                throws IOException

Called prior to modifying a table's properties. Called as part of modify table RPC call.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; currentDescriptor - current TableDescriptor of the table; newDescriptor - after modify operation, table will have this descriptor
Throws:: IOException

postModifyTable

@Deprecated
default void postModifyTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                         TableName tableName,
                                         TableDescriptor currentDescriptor)
                                  throws IOException

Deprecated. Since 2.1. Will be removed in 3.0.

Called after the modifyTable operation has been requested. Called as part of modify table RPC call.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; currentDescriptor - current TableDescriptor of the table
Throws:: IOException

postModifyTable

default void postModifyTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             TableName tableName,
                             TableDescriptor oldDescriptor,
                             TableDescriptor currentDescriptor)
                      throws IOException

Called after the modifyTable operation has been requested. Called as part of modify table RPC call.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; oldDescriptor - descriptor of table before modify operation happened; currentDescriptor - current TableDescriptor of the table
Throws:: IOException

preModifyTableAction

@Deprecated
default void preModifyTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                              TableName tableName,
                                              TableDescriptor newDescriptor)
                                       throws IOException

Deprecated. Since 2.1. Will be removed in 3.0.

Called prior to modifying a table's properties. Called as part of modify table procedure and it is async to the modify table RPC call.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; newDescriptor - after modify operation, table will have this descriptor
Throws:: IOException

preModifyTableAction

default void preModifyTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                  TableName tableName,
                                  TableDescriptor currentDescriptor,
                                  TableDescriptor newDescriptor)
                           throws IOException

Called prior to modifying a table's properties. Called as part of modify table procedure and it is async to the modify table RPC call.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; currentDescriptor - current TableDescriptor of the table; newDescriptor - after modify operation, table will have this descriptor
Throws:: IOException

postCompletedModifyTableAction

@Deprecated
default void postCompletedModifyTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                                        TableName tableName,
                                                        TableDescriptor currentDescriptor)
                                                 throws IOException

Deprecated. Since 2.1. Will be removed in 3.0.

Called after to modifying a table's properties. Called as part of modify table procedure and it is async to the modify table RPC call.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; currentDescriptor - current TableDescriptor of the table
Throws:: IOException

postCompletedModifyTableAction

default void postCompletedModifyTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                            TableName tableName,
                                            TableDescriptor oldDescriptor,
                                            TableDescriptor currentDescriptor)
                                     throws IOException

Called after to modifying a table's properties. Called as part of modify table procedure and it is async to the modify table RPC call.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; oldDescriptor - descriptor of table before modify operation happened; currentDescriptor - current TableDescriptor of the table
Throws:: IOException

preEnableTable
```
default void preEnableTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                            TableName tableName)
                     throws IOException
```
Called prior to enabling a table. Called as part of enable table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

postEnableTable
```
default void postEnableTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             TableName tableName)
                      throws IOException
```
Called after the enableTable operation has been requested. Called as part of enable table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

preEnableTableAction
```
default void preEnableTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                  TableName tableName)
                           throws IOException
```
Called prior to enabling a table. Called as part of enable table procedure and it is async to the enable table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

postCompletedEnableTableAction
```
default void postCompletedEnableTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                            TableName tableName)
                                     throws IOException
```
Called after the enableTable operation has been requested. Called as part of enable table procedure and it is async to the enable table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

preDisableTable
```
default void preDisableTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             TableName tableName)
                      throws IOException
```
Called prior to disabling a table. Called as part of disable table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

postDisableTable
```
default void postDisableTable(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              TableName tableName)
                       throws IOException
```
Called after the disableTable operation has been requested. Called as part of disable table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

preDisableTableAction
```
default void preDisableTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                   TableName tableName)
                            throws IOException
```
Called prior to disabling a table. Called as part of disable table procedure and it is asyn to the disable table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

postCompletedDisableTableAction
```
default void postCompletedDisableTableAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                             TableName tableName)
                                      throws IOException
```
Called after the disableTable operation has been requested. Called as part of disable table procedure and it is asyn to the disable table RPC call.

Parameters:

ctx - the environment to interact with the framework and master

tableName - the name of the table

Throws:

IOException

preAbortProcedure
```
default void preAbortProcedure(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               long procId)
                        throws IOException
```
Called before a abortProcedure request has been processed.

Parameters:

ctx - the environment to interact with the framework and master

procId - the Id of the procedure

Throws:

IOException

postAbortProcedure
```
default void postAbortProcedure(ObserverContext<MasterCoprocessorEnvironment> ctx)
                         throws IOException
```
Called after a abortProcedure request has been processed.

Parameters:

ctx - the environment to interact with the framework and master

Throws:

IOException

preGetProcedures
```
default void preGetProcedures(ObserverContext<MasterCoprocessorEnvironment> ctx)
                       throws IOException
```
Called before a getProcedures request has been processed.

Parameters:

ctx - the environment to interact with the framework and master

Throws:

IOException

postGetProcedures
```
default void postGetProcedures(ObserverContext<MasterCoprocessorEnvironment> ctx)
                        throws IOException
```
Called after a getProcedures request has been processed.

Parameters:

ctx - the environment to interact with the framework and master

Throws:

IOException

preGetLocks
```
default void preGetLocks(ObserverContext<MasterCoprocessorEnvironment> ctx)
                  throws IOException
```
Called before a getLocks request has been processed.

Parameters:

ctx - the environment to interact with the framework and master

Throws:

IOException - if something went wrong

postGetLocks
```
default void postGetLocks(ObserverContext<MasterCoprocessorEnvironment> ctx)
                   throws IOException
```
Called after a getLocks request has been processed.

Parameters:

ctx - the environment to interact with the framework and master

Throws:

IOException - if something went wrong

preMove

default void preMove(ObserverContext<MasterCoprocessorEnvironment> ctx,
                     RegionInfo region,
                     ServerName srcServer,
                     ServerName destServer)
              throws IOException

Called prior to moving a given region from one region server to another.

Parameters:: ctx - the environment to interact with the framework and master; region - the RegionInfo; srcServer - the source ServerName; destServer - the destination ServerName
Throws:: IOException

postMove

default void postMove(ObserverContext<MasterCoprocessorEnvironment> ctx,
                      RegionInfo region,
                      ServerName srcServer,
                      ServerName destServer)
               throws IOException

Called after the region move has been requested.

Parameters:: ctx - the environment to interact with the framework and master; region - the RegionInfo; srcServer - the source ServerName; destServer - the destination ServerName
Throws:: IOException

preAssign

default void preAssign(ObserverContext<MasterCoprocessorEnvironment> ctx,
                       RegionInfo regionInfo)
                throws IOException

Called prior to assigning a specific region.

Parameters:: ctx - the environment to interact with the framework and master; regionInfo - the regionInfo of the region
Throws:: IOException

postAssign
```
default void postAssign(ObserverContext<MasterCoprocessorEnvironment> ctx,
                        RegionInfo regionInfo)
                 throws IOException
```
Called after the region assignment has been requested.

Parameters:

ctx - the environment to interact with the framework and master

regionInfo - the regionInfo of the region

Throws:

IOException

preUnassign

default void preUnassign(ObserverContext<MasterCoprocessorEnvironment> ctx,
                         RegionInfo regionInfo,
                         boolean force)
                  throws IOException

Called prior to unassigning a given region.

Parameters:: ctx - the environment to interact with the framework and master; regionInfo -; force - whether to force unassignment or not
Throws:: IOException

postUnassign

default void postUnassign(ObserverContext<MasterCoprocessorEnvironment> ctx,
                          RegionInfo regionInfo,
                          boolean force)
                   throws IOException

Called after the region unassignment has been requested.

Parameters:: ctx - the environment to interact with the framework and master; regionInfo -; force - whether to force unassignment or not
Throws:: IOException

preRegionOffline

default void preRegionOffline(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              RegionInfo regionInfo)
                       throws IOException

Called prior to marking a given region as offline.

Parameters:: ctx - the environment to interact with the framework and master; regionInfo -
Throws:: IOException

postRegionOffline

default void postRegionOffline(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               RegionInfo regionInfo)
                        throws IOException

Called after the region has been marked offline.

Parameters:: ctx - the environment to interact with the framework and master; regionInfo -
Throws:: IOException

preBalance
```
default void preBalance(ObserverContext<MasterCoprocessorEnvironment> ctx)
                 throws IOException
```
Called prior to requesting rebalancing of the cluster regions, though after the initial checks for regions in transition and the balance switch flag.

Parameters:

ctx - the environment to interact with the framework and master

Throws:

IOException

postBalance
```
default void postBalance(ObserverContext<MasterCoprocessorEnvironment> ctx,
                         List<RegionPlan> plans)
                  throws IOException
```
Called after the balancing plan has been submitted.

Parameters:

ctx - the environment to interact with the framework and master

plans - the RegionPlans which master has executed. RegionPlan serves as hint as for the final destination for the underlying region but may not represent the final state of assignment

Throws:

IOException

preSetSplitOrMergeEnabled

default void preSetSplitOrMergeEnabled(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                       boolean newValue,
                                       MasterSwitchType switchType)
                                throws IOException

Called prior to setting split / merge switch Supports Coprocessor 'bypass'.

Parameters:: ctx - the coprocessor instance's environment; newValue - the new value submitted in the call; switchType - type of switch
Throws:: IOException

postSetSplitOrMergeEnabled

default void postSetSplitOrMergeEnabled(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                        boolean newValue,
                                        MasterSwitchType switchType)
                                 throws IOException

Called after setting split / merge switch

Parameters:: ctx - the coprocessor instance's environment; newValue - the new value submitted in the call; switchType - type of switch
Throws:: IOException

preSplitRegion

default void preSplitRegion(ObserverContext<MasterCoprocessorEnvironment> c,
                            TableName tableName,
                            byte[] splitRow)
                     throws IOException

Called before the split region procedure is called.

Parameters:: c - the environment to interact with the framework and master; tableName - the table where the region belongs to; splitRow - split point
Throws:: IOException

preSplitRegionAction

default void preSplitRegionAction(ObserverContext<MasterCoprocessorEnvironment> c,
                                  TableName tableName,
                                  byte[] splitRow)
                           throws IOException

Called before the region is split.

Parameters:: c - the environment to interact with the framework and master; tableName - the table where the region belongs to; splitRow - split point
Throws:: IOException

postCompletedSplitRegionAction

default void postCompletedSplitRegionAction(ObserverContext<MasterCoprocessorEnvironment> c,
                                            RegionInfo regionInfoA,
                                            RegionInfo regionInfoB)
                                     throws IOException

Called after the region is split.

Parameters:: c - the environment to interact with the framework and master; regionInfoA - the left daughter region; regionInfoB - the right daughter region
Throws:: IOException

preSplitRegionBeforeMETAAction

default void preSplitRegionBeforeMETAAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                            byte[] splitKey,
                                            List<Mutation> metaEntries)
                                     throws IOException

This will be called before update META step as part of split transaction.

Parameters:: ctx - the environment to interact with the framework and master; splitKey -; metaEntries -
Throws:: IOException

preSplitRegionAfterMETAAction
```
default void preSplitRegionAfterMETAAction(ObserverContext<MasterCoprocessorEnvironment> ctx)
                                    throws IOException
```
This will be called after update META step as part of split transaction

Parameters:

ctx - the environment to interact with the framework and master

Throws:

IOException

postRollBackSplitRegionAction
```
default void postRollBackSplitRegionAction(ObserverContext<MasterCoprocessorEnvironment> ctx)
                                    throws IOException
```
This will be called after the roll back of the split region is completed

Parameters:

ctx - the environment to interact with the framework and master

Throws:

IOException

preMergeRegionsAction

default void preMergeRegionsAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                   RegionInfo[] regionsToMerge)
                            throws IOException

Called before the regions merge.

Parameters:: ctx - the environment to interact with the framework and master
Throws:: IOException

postCompletedMergeRegionsAction

default void postCompletedMergeRegionsAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                             RegionInfo[] regionsToMerge,
                                             RegionInfo mergedRegion)
                                      throws IOException

called after the regions merge.

Parameters:: ctx - the environment to interact with the framework and master
Throws:: IOException

preMergeRegionsCommitAction

default void preMergeRegionsCommitAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                         RegionInfo[] regionsToMerge,
                                         @MetaMutationAnnotation
                                         List<Mutation> metaEntries)
                                  throws IOException

This will be called before update META step as part of regions merge transaction.

Parameters:: ctx - the environment to interact with the framework and master; metaEntries - mutations to execute on hbase:meta atomically with regions merge updates. Any puts or deletes to execute on hbase:meta can be added to the mutations.
Throws:: IOException

postMergeRegionsCommitAction

default void postMergeRegionsCommitAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                          RegionInfo[] regionsToMerge,
                                          RegionInfo mergedRegion)
                                   throws IOException

This will be called after META step as part of regions merge transaction.

Parameters:: ctx - the environment to interact with the framework and master
Throws:: IOException

postRollBackMergeRegionsAction

default void postRollBackMergeRegionsAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                            RegionInfo[] regionsToMerge)
                                     throws IOException

This will be called after the roll back of the regions merge.

Parameters:: ctx - the environment to interact with the framework and master
Throws:: IOException

preBalanceSwitch

default void preBalanceSwitch(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              boolean newValue)
                       throws IOException

Called prior to modifying the flag used to enable/disable region balancing.

Parameters:: ctx - the coprocessor instance's environment
Throws:: IOException

postBalanceSwitch
```
default void postBalanceSwitch(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               boolean oldValue,
                               boolean newValue)
                        throws IOException
```
Called after the flag to enable/disable balancing has changed.

Parameters:

ctx - the coprocessor instance's environment

oldValue - the previously set balanceSwitch value

newValue - the newly set balanceSwitch value

Throws:

IOException

preShutdown

default void preShutdown(ObserverContext<MasterCoprocessorEnvironment> ctx)
                  throws IOException

Called prior to shutting down the full HBase cluster, including this HMaster process.

Throws:: IOException

preStopMaster

default void preStopMaster(ObserverContext<MasterCoprocessorEnvironment> ctx)
                    throws IOException

Called immediately prior to stopping this HMaster process.

Throws:: IOException

postStartMaster
```
default void postStartMaster(ObserverContext<MasterCoprocessorEnvironment> ctx)
                      throws IOException
```
Called immediately after an active master instance has completed initialization. Will not be called on standby master instances unless they take over the active role.

Throws:

IOException

preMasterInitialization

default void preMasterInitialization(ObserverContext<MasterCoprocessorEnvironment> ctx)
                              throws IOException

Call before the master initialization is set to true. HMaster process.

Throws:: IOException

preSnapshot

default void preSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                         SnapshotDescription snapshot,
                         TableDescriptor tableDescriptor)
                  throws IOException

Called before a new snapshot is taken. Called as part of snapshot RPC call.

Parameters:: ctx - the environment to interact with the framework and master; snapshot - the SnapshotDescriptor for the snapshot; tableDescriptor - the TableDescriptor of the table to snapshot
Throws:: IOException

postSnapshot
```
default void postSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                          SnapshotDescription snapshot,
                          TableDescriptor tableDescriptor)
                   throws IOException
```
Called after the snapshot operation has been requested. Called as part of snapshot RPC call.

Parameters:

ctx - the environment to interact with the framework and master

snapshot - the SnapshotDescriptor for the snapshot

tableDescriptor - the TableDescriptor of the table to snapshot

Throws:

IOException

postCompletedSnapshotAction

default void postCompletedSnapshotAction(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                         SnapshotDescription snapshot,
                                         TableDescriptor tableDescriptor)
                                  throws IOException

Called after the snapshot operation has been completed.

Parameters:: ctx - the environment to interact with the framework and master; snapshot - the SnapshotDescriptor for the snapshot; tableDescriptor - the TableDescriptor of the table to snapshot
Throws:: IOException

preListSnapshot

default void preListSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             SnapshotDescription snapshot)
                      throws IOException

Called before listSnapshots request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; snapshot - the SnapshotDescriptor of the snapshot to list
Throws:: IOException

postListSnapshot

default void postListSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              SnapshotDescription snapshot)
                       throws IOException

Called after listSnapshots request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; snapshot - the SnapshotDescriptor of the snapshot to list
Throws:: IOException

preCloneSnapshot

default void preCloneSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              SnapshotDescription snapshot,
                              TableDescriptor tableDescriptor)
                       throws IOException

Called before a snapshot is cloned. Called as part of restoreSnapshot RPC call.

Parameters:: ctx - the environment to interact with the framework and master; snapshot - the SnapshotDescriptor for the snapshot; tableDescriptor - the TableDescriptor of the table to create
Throws:: IOException

postCloneSnapshot

default void postCloneSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               SnapshotDescription snapshot,
                               TableDescriptor tableDescriptor)
                        throws IOException

Called after a snapshot clone operation has been requested. Called as part of restoreSnapshot RPC call.

Parameters:: ctx - the environment to interact with the framework and master; snapshot - the SnapshotDescriptor for the snapshot; tableDescriptor - the v of the table to create
Throws:: IOException

preRestoreSnapshot

default void preRestoreSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                SnapshotDescription snapshot,
                                TableDescriptor tableDescriptor)
                         throws IOException

Called before a snapshot is restored. Called as part of restoreSnapshot RPC call.

Parameters:: ctx - the environment to interact with the framework and master; snapshot - the SnapshotDescriptor for the snapshot; tableDescriptor - the TableDescriptor of the table to restore
Throws:: IOException

postRestoreSnapshot

default void postRestoreSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                 SnapshotDescription snapshot,
                                 TableDescriptor tableDescriptor)
                          throws IOException

Called after a snapshot restore operation has been requested. Called as part of restoreSnapshot RPC call.

Parameters:: ctx - the environment to interact with the framework and master; snapshot - the SnapshotDescriptor for the snapshot; tableDescriptor - the TableDescriptor of the table to restore
Throws:: IOException

preDeleteSnapshot
```
default void preDeleteSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               SnapshotDescription snapshot)
                        throws IOException
```
Called before a snapshot is deleted. Called as part of deleteSnapshot RPC call.

Parameters:

ctx - the environment to interact with the framework and master

snapshot - the SnapshotDescriptor of the snapshot to delete

Throws:

IOException

postDeleteSnapshot
```
default void postDeleteSnapshot(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                SnapshotDescription snapshot)
                         throws IOException
```
Called after the delete snapshot operation has been requested. Called as part of deleteSnapshot RPC call.

Parameters:

ctx - the environment to interact with the framework and master

snapshot - the SnapshotDescriptor of the snapshot to delete

Throws:

IOException

preGetTableDescriptors

default void preGetTableDescriptors(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                    List<TableName> tableNamesList,
                                    List<TableDescriptor> descriptors,
                                    String regex)
                             throws IOException

Called before a getTableDescriptors request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; tableNamesList - the list of table names, or null if querying for all; descriptors - an empty list, can be filled with what to return in coprocessor; regex - regular expression used for filtering the table names
Throws:: IOException

postGetTableDescriptors

default void postGetTableDescriptors(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                     List<TableName> tableNamesList,
                                     List<TableDescriptor> descriptors,
                                     String regex)
                              throws IOException

Called after a getTableDescriptors request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; tableNamesList - the list of table names, or null if querying for all; descriptors - the list of descriptors about to be returned; regex - regular expression used for filtering the table names
Throws:: IOException

preGetTableNames

default void preGetTableNames(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              List<TableDescriptor> descriptors,
                              String regex)
                       throws IOException

Called before a getTableNames request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; descriptors - an empty list, can be filled with what to return by coprocessor; regex - regular expression used for filtering the table names
Throws:: IOException

postGetTableNames

default void postGetTableNames(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               List<TableDescriptor> descriptors,
                               String regex)
                        throws IOException

Called after a getTableNames request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; descriptors - the list of descriptors about to be returned; regex - regular expression used for filtering the table names
Throws:: IOException

preCreateNamespace

default void preCreateNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                NamespaceDescriptor ns)
                         throws IOException

Called before a new namespace is created by HMaster.

Parameters:: ctx - the environment to interact with the framework and master; ns - the NamespaceDescriptor for the table
Throws:: IOException

postCreateNamespace

default void postCreateNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                 NamespaceDescriptor ns)
                          throws IOException

Called after the createNamespace operation has been requested.

Parameters:: ctx - the environment to interact with the framework and master; ns - the NamespaceDescriptor for the table
Throws:: IOException

preDeleteNamespace

default void preDeleteNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                String namespace)
                         throws IOException

Called before HMaster deletes a namespace

Parameters:: ctx - the environment to interact with the framework and master; namespace - the name of the namespace
Throws:: IOException

postDeleteNamespace

default void postDeleteNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                 String namespace)
                          throws IOException

Called after the deleteNamespace operation has been requested.

Parameters:: ctx - the environment to interact with the framework and master; namespace - the name of the namespace
Throws:: IOException

preModifyNamespace

@Deprecated
default void preModifyNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                            NamespaceDescriptor newNsDescriptor)
                                     throws IOException

Deprecated. Since 2.1. Will be removed in 3.0.

Called prior to modifying a namespace's properties.

Parameters:: ctx - the environment to interact with the framework and master; newNsDescriptor - after modify operation, namespace will have this descriptor
Throws:: IOException

preModifyNamespace

default void preModifyNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                NamespaceDescriptor currentNsDescriptor,
                                NamespaceDescriptor newNsDescriptor)
                         throws IOException

Called prior to modifying a namespace's properties.

Parameters:: ctx - the environment to interact with the framework and master; currentNsDescriptor - current NamespaceDescriptor of the namespace; newNsDescriptor - after modify operation, namespace will have this descriptor
Throws:: IOException

postModifyNamespace

@Deprecated
default void postModifyNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                             NamespaceDescriptor currentNsDescriptor)
                                      throws IOException

Deprecated. Since 2.1. Will be removed in 3.0.

Called after the modifyNamespace operation has been requested.

Parameters:: ctx - the environment to interact with the framework and master; currentNsDescriptor - current NamespaceDescriptor of the namespace
Throws:: IOException

postModifyNamespace

default void postModifyNamespace(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                 NamespaceDescriptor oldNsDescriptor,
                                 NamespaceDescriptor currentNsDescriptor)
                          throws IOException

Called after the modifyNamespace operation has been requested.

Parameters:: ctx - the environment to interact with the framework and master; oldNsDescriptor - descriptor of namespace before modify operation happened; currentNsDescriptor - current NamespaceDescriptor of the namespace
Throws:: IOException

preGetNamespaceDescriptor

default void preGetNamespaceDescriptor(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                       String namespace)
                                throws IOException

Called before a getNamespaceDescriptor request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; namespace - the name of the namespace
Throws:: IOException

postGetNamespaceDescriptor

default void postGetNamespaceDescriptor(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                        NamespaceDescriptor ns)
                                 throws IOException

Called after a getNamespaceDescriptor request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; ns - the NamespaceDescriptor
Throws:: IOException

preListNamespaces
```
default void preListNamespaces(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               List<String> namespaces)
                        throws IOException
```
Called before a listNamespaces request has been processed.

Parameters:

ctx - the environment to interact with the framework and master

namespaces - an empty list, can be filled with what to return if bypassing

Throws:

IOException - if something went wrong

postListNamespaces
```
default void postListNamespaces(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                List<String> namespaces)
                         throws IOException
```
Called after a listNamespaces request has been processed.

Parameters:

ctx - the environment to interact with the framework and master

namespaces - the list of namespaces about to be returned

Throws:

IOException - if something went wrong

preListNamespaceDescriptors

default void preListNamespaceDescriptors(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                         List<NamespaceDescriptor> descriptors)
                                  throws IOException

Called before a listNamespaceDescriptors request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; descriptors - an empty list, can be filled with what to return by coprocessor
Throws:: IOException

postListNamespaceDescriptors

default void postListNamespaceDescriptors(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                          List<NamespaceDescriptor> descriptors)
                                   throws IOException

Called after a listNamespaceDescriptors request has been processed.

Parameters:: ctx - the environment to interact with the framework and master; descriptors - the list of descriptors about to be returned
Throws:: IOException

preTableFlush

default void preTableFlush(ObserverContext<MasterCoprocessorEnvironment> ctx,
                           TableName tableName)
                    throws IOException

Called before the table memstore is flushed to disk.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table
Throws:: IOException

postTableFlush

default void postTableFlush(ObserverContext<MasterCoprocessorEnvironment> ctx,
                            TableName tableName)
                     throws IOException

Called after the table memstore is flushed to disk.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table
Throws:: IOException

preSetUserQuota

default void preSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             String userName,
                             GlobalQuotaSettings quotas)
                      throws IOException

Called before the quota for the user is stored.

Parameters:: ctx - the environment to interact with the framework and master; userName - the name of user; quotas - the current quota for the user
Throws:: IOException

postSetUserQuota

default void postSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              String userName,
                              GlobalQuotaSettings quotas)
                       throws IOException

Called after the quota for the user is stored.

Parameters:: ctx - the environment to interact with the framework and master; userName - the name of user; quotas - the resulting quota for the user
Throws:: IOException

preSetUserQuota

default void preSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             String userName,
                             TableName tableName,
                             GlobalQuotaSettings quotas)
                      throws IOException

Called before the quota for the user on the specified table is stored.

Parameters:: ctx - the environment to interact with the framework and master; userName - the name of user; tableName - the name of the table; quotas - the current quota for the user on the table
Throws:: IOException

postSetUserQuota

default void postSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              String userName,
                              TableName tableName,
                              GlobalQuotaSettings quotas)
                       throws IOException

Called after the quota for the user on the specified table is stored.

Parameters:: ctx - the environment to interact with the framework and master; userName - the name of user; tableName - the name of the table; quotas - the resulting quota for the user on the table
Throws:: IOException

preSetUserQuota

default void preSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             String userName,
                             String namespace,
                             GlobalQuotaSettings quotas)
                      throws IOException

Called before the quota for the user on the specified namespace is stored.

Parameters:: ctx - the environment to interact with the framework and master; userName - the name of user; namespace - the name of the namespace; quotas - the current quota for the user on the namespace
Throws:: IOException

postSetUserQuota

default void postSetUserQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              String userName,
                              String namespace,
                              GlobalQuotaSettings quotas)
                       throws IOException

Called after the quota for the user on the specified namespace is stored.

Parameters:: ctx - the environment to interact with the framework and master; userName - the name of user; namespace - the name of the namespace; quotas - the resulting quota for the user on the namespace
Throws:: IOException

preSetTableQuota

default void preSetTableQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              TableName tableName,
                              GlobalQuotaSettings quotas)
                       throws IOException

Called before the quota for the table is stored.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; quotas - the current quota for the table
Throws:: IOException

postSetTableQuota

default void postSetTableQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               TableName tableName,
                               GlobalQuotaSettings quotas)
                        throws IOException

Called after the quota for the table is stored.

Parameters:: ctx - the environment to interact with the framework and master; tableName - the name of the table; quotas - the resulting quota for the table
Throws:: IOException

preSetNamespaceQuota

default void preSetNamespaceQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                  String namespace,
                                  GlobalQuotaSettings quotas)
                           throws IOException

Called before the quota for the namespace is stored.

Parameters:: ctx - the environment to interact with the framework and master; namespace - the name of the namespace; quotas - the current quota for the namespace
Throws:: IOException

postSetNamespaceQuota

default void postSetNamespaceQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                   String namespace,
                                   GlobalQuotaSettings quotas)
                            throws IOException

Called after the quota for the namespace is stored.

Parameters:: ctx - the environment to interact with the framework and master; namespace - the name of the namespace; quotas - the resulting quota for the namespace
Throws:: IOException

preSetRegionServerQuota

default void preSetRegionServerQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                     String regionServer,
                                     GlobalQuotaSettings quotas)
                              throws IOException

Called before the quota for the region server is stored.

Parameters:: ctx - the environment to interact with the framework and master; regionServer - the name of the region server; quotas - the current quota for the region server
Throws:: IOException

postSetRegionServerQuota

default void postSetRegionServerQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                      String regionServer,
                                      GlobalQuotaSettings quotas)
                               throws IOException

Called after the quota for the region server is stored.

Parameters:: ctx - the environment to interact with the framework and master; regionServer - the name of the region server; quotas - the resulting quota for the region server
Throws:: IOException

preMergeRegions

default void preMergeRegions(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             RegionInfo[] regionsToMerge)
                      throws IOException

Called before merge regions request.

Parameters:: ctx - coprocessor environment; regionsToMerge - regions to be merged
Throws:: IOException

postMergeRegions

default void postMergeRegions(ObserverContext<MasterCoprocessorEnvironment> c,
                              RegionInfo[] regionsToMerge)
                       throws IOException

called after merge regions request.

Parameters:: c - coprocessor environment; regionsToMerge - regions to be merged
Throws:: IOException

preMoveServersAndTables

default void preMoveServersAndTables(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                     Set<Address> servers,
                                     Set<TableName> tables,
                                     String targetGroup)
                              throws IOException

Called before servers are moved to target region server group

Parameters:: ctx - the environment to interact with the framework and master; servers - set of servers to move; targetGroup - destination group
Throws:: IOException

postMoveServersAndTables

default void postMoveServersAndTables(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                      Set<Address> servers,
                                      Set<TableName> tables,
                                      String targetGroup)
                               throws IOException

Called after servers are moved to target region server group

Parameters:: ctx - the environment to interact with the framework and master; servers - set of servers to move; targetGroup - name of group
Throws:: IOException

preMoveServers

default void preMoveServers(ObserverContext<MasterCoprocessorEnvironment> ctx,
                            Set<Address> servers,
                            String targetGroup)
                     throws IOException

Called before servers are moved to target region server group

Parameters:: ctx - the environment to interact with the framework and master; servers - set of servers to move; targetGroup - destination group
Throws:: IOException

postMoveServers

default void postMoveServers(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             Set<Address> servers,
                             String targetGroup)
                      throws IOException

Called after servers are moved to target region server group

Parameters:: ctx - the environment to interact with the framework and master; servers - set of servers to move; targetGroup - name of group
Throws:: IOException

preMoveTables

default void preMoveTables(ObserverContext<MasterCoprocessorEnvironment> ctx,
                           Set<TableName> tables,
                           String targetGroup)
                    throws IOException

Called before tables are moved to target region server group

Parameters:: ctx - the environment to interact with the framework and master; tables - set of tables to move; targetGroup - name of group
Throws:: IOException

postMoveTables

default void postMoveTables(ObserverContext<MasterCoprocessorEnvironment> ctx,
                            Set<TableName> tables,
                            String targetGroup)
                     throws IOException

Called after servers are moved to target region server group

Parameters:: ctx - the environment to interact with the framework and master; tables - set of tables to move; targetGroup - name of group
Throws:: IOException

preAddRSGroup

default void preAddRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx,
                           String name)
                    throws IOException

Called before a new region server group is added

Parameters:: ctx - the environment to interact with the framework and master; name - group name
Throws:: IOException

postAddRSGroup

default void postAddRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx,
                            String name)
                     throws IOException

Called after a new region server group is added

Parameters:: ctx - the environment to interact with the framework and master; name - group name
Throws:: IOException

preRemoveRSGroup

default void preRemoveRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              String name)
                       throws IOException

Called before a region server group is removed

Parameters:: ctx - the environment to interact with the framework and master; name - group name
Throws:: IOException

postRemoveRSGroup

default void postRemoveRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               String name)
                        throws IOException

Called after a region server group is removed

Parameters:: ctx - the environment to interact with the framework and master; name - group name
Throws:: IOException

preBalanceRSGroup

default void preBalanceRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               String groupName)
                        throws IOException

Called before a region server group is removed

Parameters:: ctx - the environment to interact with the framework and master; groupName - group name
Throws:: IOException

postBalanceRSGroup

default void postBalanceRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                String groupName,
                                boolean balancerRan)
                         throws IOException

Called after a region server group is removed

Parameters:: ctx - the environment to interact with the framework and master; groupName - group name
Throws:: IOException

preRemoveServers

default void preRemoveServers(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              Set<Address> servers)
                       throws IOException

Called before servers are removed from rsgroup

Parameters:: ctx - the environment to interact with the framework and master; servers - set of decommissioned servers to remove
Throws:: IOException

postRemoveServers

default void postRemoveServers(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               Set<Address> servers)
                        throws IOException

Called after servers are removed from rsgroup

Parameters:: ctx - the environment to interact with the framework and master; servers - set of servers to remove
Throws:: IOException

preAddReplicationPeer

default void preAddReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                   String peerId,
                                   ReplicationPeerConfig peerConfig)
                            throws IOException

Called before add a replication peer

Parameters:: ctx - the environment to interact with the framework and master; peerId - a short name that identifies the peer; peerConfig - configuration for the replication peer
Throws:: IOException

postAddReplicationPeer

default void postAddReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                    String peerId,
                                    ReplicationPeerConfig peerConfig)
                             throws IOException

Called after add a replication peer

Parameters:: ctx - the environment to interact with the framework and master; peerId - a short name that identifies the peer; peerConfig - configuration for the replication peer
Throws:: IOException

preRemoveReplicationPeer

default void preRemoveReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                      String peerId)
                               throws IOException

Called before remove a replication peer

Parameters:: ctx -; peerId - a short name that identifies the peer
Throws:: IOException

postRemoveReplicationPeer

default void postRemoveReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                       String peerId)
                                throws IOException

Called after remove a replication peer

Parameters:: ctx -; peerId - a short name that identifies the peer
Throws:: IOException

preEnableReplicationPeer

default void preEnableReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                      String peerId)
                               throws IOException

Called before enable a replication peer

Parameters:: ctx -; peerId - a short name that identifies the peer
Throws:: IOException

postEnableReplicationPeer

default void postEnableReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                       String peerId)
                                throws IOException

Called after enable a replication peer

Parameters:: ctx -; peerId - a short name that identifies the peer
Throws:: IOException

preDisableReplicationPeer

default void preDisableReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                       String peerId)
                                throws IOException

Called before disable a replication peer

Parameters:: ctx -; peerId - a short name that identifies the peer
Throws:: IOException

postDisableReplicationPeer

default void postDisableReplicationPeer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                        String peerId)
                                 throws IOException

Called after disable a replication peer

Parameters:: ctx -; peerId - a short name that identifies the peer
Throws:: IOException

preGetReplicationPeerConfig

default void preGetReplicationPeerConfig(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                         String peerId)
                                  throws IOException

Called before get the configured ReplicationPeerConfig for the specified peer

Parameters:: ctx -; peerId - a short name that identifies the peer
Throws:: IOException

postGetReplicationPeerConfig

default void postGetReplicationPeerConfig(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                          String peerId)
                                   throws IOException

Called after get the configured ReplicationPeerConfig for the specified peer

Parameters:: ctx -; peerId - a short name that identifies the peer
Throws:: IOException

preUpdateReplicationPeerConfig

default void preUpdateReplicationPeerConfig(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                            String peerId,
                                            ReplicationPeerConfig peerConfig)
                                     throws IOException

Called before update peerConfig for the specified peer

Parameters:: ctx -; peerId - a short name that identifies the peer
Throws:: IOException

postUpdateReplicationPeerConfig

default void postUpdateReplicationPeerConfig(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                             String peerId,
                                             ReplicationPeerConfig peerConfig)
                                      throws IOException

Called after update peerConfig for the specified peer

Parameters:: ctx - the environment to interact with the framework and master; peerId - a short name that identifies the peer
Throws:: IOException

preListReplicationPeers

default void preListReplicationPeers(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                     String regex)
                              throws IOException

Called before list replication peers.

Parameters:: ctx - the environment to interact with the framework and master; regex - The regular expression to match peer id
Throws:: IOException

postListReplicationPeers

default void postListReplicationPeers(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                      String regex)
                               throws IOException

Called after list replication peers.

Parameters:: ctx - the environment to interact with the framework and master; regex - The regular expression to match peer id
Throws:: IOException

preRequestLock

default void preRequestLock(ObserverContext<MasterCoprocessorEnvironment> ctx,
                            String namespace,
                            TableName tableName,
                            RegionInfo[] regionInfos,
                            String description)
                     throws IOException

Called before new LockProcedure is queued.

Parameters:: ctx - the environment to interact with the framework and master
Throws:: IOException

postRequestLock

default void postRequestLock(ObserverContext<MasterCoprocessorEnvironment> ctx,
                             String namespace,
                             TableName tableName,
                             RegionInfo[] regionInfos,
                             String description)
                      throws IOException

Called after new LockProcedure is queued.

Parameters:: ctx - the environment to interact with the framework and master
Throws:: IOException

preLockHeartbeat

default void preLockHeartbeat(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              TableName tn,
                              String description)
                       throws IOException

Called before heartbeat to a lock.

Parameters:: ctx - the environment to interact with the framework and master
Throws:: IOException

postLockHeartbeat
```
default void postLockHeartbeat(ObserverContext<MasterCoprocessorEnvironment> ctx)
                        throws IOException
```
Called after heartbeat to a lock.

Parameters:

ctx - the environment to interact with the framework and master

Throws:

IOException

preGetClusterMetrics

default void preGetClusterMetrics(ObserverContext<MasterCoprocessorEnvironment> ctx)
                           throws IOException

Called before get cluster status.

Throws:: IOException

postGetClusterMetrics

default void postGetClusterMetrics(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                   ClusterMetrics status)
                            throws IOException

Called after get cluster status.

Throws:: IOException

preClearDeadServers

default void preClearDeadServers(ObserverContext<MasterCoprocessorEnvironment> ctx)
                          throws IOException

Called before clear dead region servers.

Throws:: IOException

postClearDeadServers

default void postClearDeadServers(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                  List<ServerName> servers,
                                  List<ServerName> notClearedServers)
                           throws IOException

Called after clear dead region servers.

Throws:: IOException

preDecommissionRegionServers

default void preDecommissionRegionServers(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                          List<ServerName> servers,
                                          boolean offload)
                                   throws IOException

Called before decommission region servers.

Throws:: IOException

postDecommissionRegionServers

default void postDecommissionRegionServers(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                           List<ServerName> servers,
                                           boolean offload)
                                    throws IOException

Called after decommission region servers.

Throws:: IOException

preListDecommissionedRegionServers

default void preListDecommissionedRegionServers(ObserverContext<MasterCoprocessorEnvironment> ctx)
                                         throws IOException

Called before list decommissioned region servers.

Throws:: IOException

postListDecommissionedRegionServers

default void postListDecommissionedRegionServers(ObserverContext<MasterCoprocessorEnvironment> ctx)
                                          throws IOException

Called after list decommissioned region servers.

Throws:: IOException

preRecommissionRegionServer

default void preRecommissionRegionServer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                         ServerName server,
                                         List<byte[]> encodedRegionNames)
                                  throws IOException

Called before recommission region server.

Throws:: IOException

postRecommissionRegionServer

default void postRecommissionRegionServer(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                          ServerName server,
                                          List<byte[]> encodedRegionNames)
                                   throws IOException

Called after recommission region server.

Throws:: IOException

preSwitchRpcThrottle

default void preSwitchRpcThrottle(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                  boolean enable)
                           throws IOException

Called before switching rpc throttle enabled state.

Parameters:: ctx - the coprocessor instance's environment; enable - the rpc throttle value
Throws:: IOException

postSwitchRpcThrottle

default void postSwitchRpcThrottle(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                   boolean oldValue,
                                   boolean newValue)
                            throws IOException

Called after switching rpc throttle enabled state.

Parameters:: ctx - the coprocessor instance's environment; oldValue - the previously rpc throttle value; newValue - the newly rpc throttle value
Throws:: IOException

preIsRpcThrottleEnabled
```
default void preIsRpcThrottleEnabled(ObserverContext<MasterCoprocessorEnvironment> ctx)
                              throws IOException
```
Called before getting if is rpc throttle enabled.

Parameters:

ctx - the coprocessor instance's environment

Throws:

IOException

postIsRpcThrottleEnabled

default void postIsRpcThrottleEnabled(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                      boolean rpcThrottleEnabled)
                               throws IOException

Called after getting if is rpc throttle enabled.

Parameters:: ctx - the coprocessor instance's environment; rpcThrottleEnabled - the rpc throttle enabled value
Throws:: IOException

preSwitchExceedThrottleQuota

default void preSwitchExceedThrottleQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                          boolean enable)
                                   throws IOException

Called before switching exceed throttle quota state.

Parameters:: ctx - the coprocessor instance's environment; enable - the exceed throttle quota value
Throws:: IOException

postSwitchExceedThrottleQuota

default void postSwitchExceedThrottleQuota(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                           boolean oldValue,
                                           boolean newValue)
                                    throws IOException

Called after switching exceed throttle quota state.

Parameters:: ctx - the coprocessor instance's environment; oldValue - the previously exceed throttle quota value; newValue - the newly exceed throttle quota value
Throws:: IOException

preGrant

default void preGrant(ObserverContext<MasterCoprocessorEnvironment> ctx,
                      UserPermission userPermission,
                      boolean mergeExistingPermissions)
               throws IOException

Called before granting user permissions.

Parameters:: ctx - the coprocessor instance's environment; userPermission - the user and permissions; mergeExistingPermissions - True if merge with previous granted permissions
Throws:: IOException

postGrant

default void postGrant(ObserverContext<MasterCoprocessorEnvironment> ctx,
                       UserPermission userPermission,
                       boolean mergeExistingPermissions)
                throws IOException

Called after granting user permissions.

Parameters:: ctx - the coprocessor instance's environment; userPermission - the user and permissions; mergeExistingPermissions - True if merge with previous granted permissions
Throws:: IOException

preRevoke

default void preRevoke(ObserverContext<MasterCoprocessorEnvironment> ctx,
                       UserPermission userPermission)
                throws IOException

Called before revoking user permissions.

Parameters:: ctx - the coprocessor instance's environment; userPermission - the user and permissions
Throws:: IOException

postRevoke

default void postRevoke(ObserverContext<MasterCoprocessorEnvironment> ctx,
                        UserPermission userPermission)
                 throws IOException

Called after revoking user permissions.

Parameters:: ctx - the coprocessor instance's environment; userPermission - the user and permissions
Throws:: IOException

preGetUserPermissions

default void preGetUserPermissions(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                   String userName,
                                   String namespace,
                                   TableName tableName,
                                   byte[] family,
                                   byte[] qualifier)
                            throws IOException

Called before getting user permissions.

Parameters:: ctx - the coprocessor instance's environment; userName - the user name, null if get all user permissions; namespace - the namespace, null if don't get namespace permission; tableName - the table name, null if don't get table permission; family - the table column family, null if don't get table family permission; qualifier - the table column qualifier, null if don't get table qualifier permission
Throws:: IOException - if something went wrong

postGetUserPermissions

default void postGetUserPermissions(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                    String userName,
                                    String namespace,
                                    TableName tableName,
                                    byte[] family,
                                    byte[] qualifier)
                             throws IOException

Called after getting user permissions.

Parameters:: ctx - the coprocessor instance's environment; userName - the user name, null if get all user permissions; namespace - the namespace, null if don't get namespace permission; tableName - the table name, null if don't get table permission; family - the table column family, null if don't get table family permission; qualifier - the table column qualifier, null if don't get table qualifier permission
Throws:: IOException - if something went wrong

preHasUserPermissions

default void preHasUserPermissions(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                   String userName,
                                   List<Permission> permissions)
                            throws IOException

Throws:: IOException

postHasUserPermissions

default void postHasUserPermissions(ObserverContext<MasterCoprocessorEnvironment> ctx,
                                    String userName,
                                    List<Permission> permissions)
                             throws IOException

Called after checking if user has permissions.

Parameters:: ctx - the coprocessor instance's environment; userName - the user name; permissions - the permission list
Throws:: IOException

preRenameRSGroup

default void preRenameRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx,
                              String oldName,
                              String newName)
                       throws IOException

Called before rename rsgroup.

Parameters:: ctx - the environment to interact with the framework and master; oldName - old rsgroup name; newName - new rsgroup name
Throws:: IOException - on failure

postRenameRSGroup

default void postRenameRSGroup(ObserverContext<MasterCoprocessorEnvironment> ctx,
                               String oldName,
                               String newName)
                        throws IOException

Called after rename rsgroup.

Parameters:: ctx - the environment to interact with the framework and master; oldName - old rsgroup name; newName - new rsgroup name
Throws:: IOException - on failure

Interface MasterObserver

Exception Handling

Method Summary

Method Detail

preCreateTableRegionsInfos

preCreateTable

postCreateTable

preCreateTableAction

postCompletedCreateTableAction

preDeleteTable

postDeleteTable

preDeleteTableAction

postCompletedDeleteTableAction

preTruncateTable

postTruncateTable

preTruncateTableAction

postCompletedTruncateTableAction

preModifyTable

preModifyTable

postModifyTable

postModifyTable

preModifyTableAction

preModifyTableAction

postCompletedModifyTableAction

postCompletedModifyTableAction

preEnableTable

postEnableTable

preEnableTableAction

postCompletedEnableTableAction

preDisableTable

postDisableTable

preDisableTableAction

postCompletedDisableTableAction

preAbortProcedure

postAbortProcedure

preGetProcedures

postGetProcedures

preGetLocks

postGetLocks

preMove

postMove

preAssign

postAssign

preUnassign

postUnassign

preRegionOffline

postRegionOffline

preBalance

postBalance

preSetSplitOrMergeEnabled

postSetSplitOrMergeEnabled

preSplitRegion

preSplitRegionAction

postCompletedSplitRegionAction

preSplitRegionBeforeMETAAction

preSplitRegionAfterMETAAction

postRollBackSplitRegionAction

preMergeRegionsAction

postCompletedMergeRegionsAction

preMergeRegionsCommitAction

postMergeRegionsCommitAction

postRollBackMergeRegionsAction

preBalanceSwitch

postBalanceSwitch

preShutdown

preStopMaster

postStartMaster

preMasterInitialization

preSnapshot

postSnapshot

postCompletedSnapshotAction

preListSnapshot

postListSnapshot

preCloneSnapshot

postCloneSnapshot

preRestoreSnapshot

postRestoreSnapshot

preDeleteSnapshot

postDeleteSnapshot

preGetTableDescriptors