Package org.apache.hadoop.hbase.master

Class MasterStateStore

java.lang.Object

org.apache.hadoop.hbase.master.MasterStateStore

Direct Known Subclasses:

BooleanStateStore

@Private
public abstract class MasterStateStore
extends Object

A state storage which stores the state in master local region.

We used to store some persistent state on zookeeper, so here we provide the ability to migrate the state from zookeeper.

Since parsing the state may introduce some extra overhead, we make this class abstract and the get and set state methods protected. Sub classes should store their state in decoded format to save the extra parsing overhead.

Field Summary

Fields

Modifier and Type	Field	Description
private static final org.slf4j.Logger	LOG
private final MasterRegion	masterRegion
private static final byte[]	QUALIFIER
private final byte[]	stateName

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	MasterStateStore(MasterRegion masterRegion, String stateName, ZKWatcher watcher, String zkPath)

Method Summary

Modifier and Type	Method	Description
private Result	get()
protected final byte[]	getState()
private byte[]	migrate(ZKWatcher watcher, String zkPath)
protected final void	setState(byte[] state)
private void	tryMigrate(ZKWatcher watcher, String zkPath)
private void	update(byte[] s)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

LOG

private static final org.slf4j.Logger LOG

QUALIFIER

private static final byte[] QUALIFIER

masterRegion

private final MasterRegion masterRegion

stateName

private final byte[] stateName

Constructor Details

MasterStateStore

protected MasterStateStore(MasterRegion masterRegion,
 String stateName,
 ZKWatcher watcher,
 String zkPath)
                    throws IOException,
org.apache.zookeeper.KeeperException

Throws:

IOException

org.apache.zookeeper.KeeperException

Method Details

getState

protected final byte[] getState()
                         throws IOException

Throws:

IOException

setState

protected final void setState(byte[] state)
                       throws IOException

Throws:

IOException

get

private Result get()
            throws IOException

Throws:

IOException

update

private void update(byte[] s)
             throws IOException

Throws:

IOException

migrate

private byte[] migrate(ZKWatcher watcher,
 String zkPath)
                throws org.apache.zookeeper.KeeperException,
IOException

Throws:

org.apache.zookeeper.KeeperException

IOException

tryMigrate

private void tryMigrate(ZKWatcher watcher,
 String zkPath)
                 throws IOException,
org.apache.zookeeper.KeeperException

Throws:

IOException

org.apache.zookeeper.KeeperException