ZKTableStateClientSideReader (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.zookeeper.ZKTableStateClientSideReader

```
@InterfaceAudience.Private
public class ZKTableStateClientSideReader
extends Object
```
Non-instantiable class that provides helper functions to learn about HBase table state for code running on client side (hence, not having access to consensus context). Doesn't cache any table state, just goes directly to ZooKeeper. TODO: decouple this class from ZooKeeper.

Constructor Summary

Constructors
Modifier Constructor and Description

private ZKTableStateClientSideReader()

Constructors
Modifier	Constructor and Description
`private`	`ZKTableStateClientSideReader()`

Method Summary

Methods
Modifier and Type	Method and Description
`static Set<TableName>`	`getDisabledOrDisablingTables(ZooKeeperWatcher zkw)` Gets a list of all the tables set as disabled in zookeeper.
`static Set<TableName>`	`getDisabledTables(ZooKeeperWatcher zkw)` Gets a list of all the tables set as disabled in zookeeper.
`static Set<TableName>`	`getEnablingTables(ZooKeeperWatcher zkw)` Gets a list of all the tables set as enabling in zookeeper.
`private static Set<TableName>`	`getTablesInStates(ZooKeeperWatcher zkw, org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos.Table.State... states)` Gets a list of tables that are set as one of the passing in states in zookeeper.
`(package private) static org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos.Table.State`	`getTableState(ZooKeeperWatcher zkw, TableName tableName)`
`static boolean`	`isDisabledTable(ZooKeeperWatcher zkw, TableName tableName)` Go to zookeeper and see if state of table is `ZooKeeperProtos.Table.State#DISABLED`.
`static boolean`	`isDisablingOrDisabledTable(ZooKeeperWatcher zkw, TableName tableName)` Go to zookeeper and see if state of table is `ZooKeeperProtos.Table.State#DISABLING` of `ZooKeeperProtos.Table.State#DISABLED`.
`static boolean`	`isEnabledTable(ZooKeeperWatcher zkw, TableName tableName)` Go to zookeeper and see if state of table is `ZooKeeperProtos.Table.State#ENABLED`.
`(package private) static boolean`	`isTableState(org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos.Table.State expectedState, org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos.Table.State currentState)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- ZKTableStateClientSideReader
```
private ZKTableStateClientSideReader()
```

Method Detail

isDisabledTable
```
public static boolean isDisabledTable(ZooKeeperWatcher zkw,
                      TableName tableName)
                               throws org.apache.zookeeper.KeeperException,
                                      InterruptedException
```
Go to zookeeper and see if state of table is ZooKeeperProtos.Table.State#DISABLED. This method does not use cache. This method is for clients other than AssignmentManager

Parameters:
zkw - ZooKeeperWatcher instance to use
tableName - table we're checking

Returns:
True if table is enabled.

Throws:

org.apache.zookeeper.KeeperException

InterruptedException

isEnabledTable
```
public static boolean isEnabledTable(ZooKeeperWatcher zkw,
                     TableName tableName)
                              throws org.apache.zookeeper.KeeperException,
                                     InterruptedException
```
Go to zookeeper and see if state of table is ZooKeeperProtos.Table.State#ENABLED. This method does not use cache. This method is for clients other than AssignmentManager

Parameters:
zkw - ZooKeeperWatcher instance to use
tableName - table we're checking

Returns:
True if table is enabled.

Throws:

org.apache.zookeeper.KeeperException

InterruptedException

isDisablingOrDisabledTable
```
public static boolean isDisablingOrDisabledTable(ZooKeeperWatcher zkw,
                                 TableName tableName)
                                          throws org.apache.zookeeper.KeeperException,
                                                 InterruptedException
```
Go to zookeeper and see if state of table is ZooKeeperProtos.Table.State#DISABLING of ZooKeeperProtos.Table.State#DISABLED. This method does not use cache. This method is for clients other than AssignmentManager.

Parameters:
zkw - ZooKeeperWatcher instance to use
tableName - table we're checking

Returns:
True if table is enabled.

Throws:

org.apache.zookeeper.KeeperException

InterruptedException

getDisabledTables

public static Set<TableName> getDisabledTables(ZooKeeperWatcher zkw)
                                        throws org.apache.zookeeper.KeeperException,
                                               InterruptedException

Gets a list of all the tables set as disabled in zookeeper.

Returns:: Set of disabled tables, empty Set if none
Throws:: org.apache.zookeeper.KeeperException; InterruptedException

getDisabledOrDisablingTables

public static Set<TableName> getDisabledOrDisablingTables(ZooKeeperWatcher zkw)
                                                   throws org.apache.zookeeper.KeeperException,
                                                          InterruptedException

Gets a list of all the tables set as disabled in zookeeper.

Returns:: Set of disabled tables, empty Set if none
Throws:: org.apache.zookeeper.KeeperException; InterruptedException

getEnablingTables

public static Set<TableName> getEnablingTables(ZooKeeperWatcher zkw)
                                        throws org.apache.zookeeper.KeeperException,
                                               InterruptedException

Gets a list of all the tables set as enabling in zookeeper.

Parameters:: zkw - ZooKeeperWatcher instance to use
Returns:: Set of enabling tables, empty Set if none
Throws:: org.apache.zookeeper.KeeperException; InterruptedException

getTablesInStates

private static Set<TableName> getTablesInStates(ZooKeeperWatcher zkw,
                               org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos.Table.State... states)
                                         throws org.apache.zookeeper.KeeperException,
                                                InterruptedException

Gets a list of tables that are set as one of the passing in states in zookeeper.

Parameters:: zkw - ZooKeeperWatcher instance to use; states - the list of states that a table could be in
Returns:: Set of tables in one of the states, empty Set if none
Throws:: org.apache.zookeeper.KeeperException; InterruptedException

isTableState

static boolean isTableState(org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos.Table.State expectedState,
                   org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos.Table.State currentState)

getTableState

static org.apache.hadoop.hbase.protobuf.generated.ZooKeeperProtos.Table.State getTableState(ZooKeeperWatcher zkw,
                                                                                   TableName tableName)
                                                                                     throws org.apache.zookeeper.KeeperException,
                                                                                            InterruptedException

Parameters:: zkw - ZooKeeperWatcher instance to use; tableName - table we're checking
Returns:: Null or ZooKeeperProtos.Table.State found in znode.
Throws:: org.apache.zookeeper.KeeperException; InterruptedException

Class ZKTableStateClientSideReader

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ZKTableStateClientSideReader