org.apache.hadoop.hbase.util

类 IdLock

java.lang.Object

org.apache.hadoop.hbase.util.IdLock

@InterfaceAudience.Private
public class IdLock
extends Object

Allows multiple concurrent clients to lock on a numeric id with a minimal memory overhead. The intended usage is as follows:

 IdLock.Entry lockEntry = idLock.getLockEntry(id);
 try {
   // User code.
 } finally {
   idLock.releaseLockEntry(lockEntry);
 }

嵌套类概要

嵌套类

限定符和类型	类和说明
static class	IdLock.Entry An entry returned to the client as a lock object

构造器概要

构造器

构造器和说明
IdLock()

方法概要

限定符和类型	方法和说明
IdLock.Entry	getLockEntry(long id) Blocks until the lock corresponding to the given id is acquired.
boolean	isHeldByCurrentThread(long id) Test whether the given id is already locked by the current thread.
void	releaseLockEntry(IdLock.Entry entry) Must be called in a finally block to decrease the internal counter and remove the monitor object for the given id if the caller is the last client.
IdLock.Entry	tryLockEntry(long id, long time) Blocks until the lock corresponding to the given id is acquired.
void	waitForWaiters(long id, int numWaiters)

从类继承的方法 java.lang.Object

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

构造器详细资料

IdLock

public IdLock()

方法详细资料

getLockEntry

public IdLock.Entry getLockEntry(long id)
                          throws IOException

Blocks until the lock corresponding to the given id is acquired.

参数:

id - an arbitrary number to lock on

返回:

an "entry" to pass to releaseLockEntry(Entry) to release the lock

抛出:

IOException - if interrupted

tryLockEntry

public IdLock.Entry tryLockEntry(long id,
                                 long time)
                          throws IOException

Blocks until the lock corresponding to the given id is acquired.

参数:

id - an arbitrary number to lock on

time - time to wait in ms

返回:

an "entry" to pass to releaseLockEntry(Entry) to release the lock

抛出:

IOException - if interrupted

releaseLockEntry

public void releaseLockEntry(IdLock.Entry entry)

Must be called in a finally block to decrease the internal counter and remove the monitor object for the given id if the caller is the last client.

参数:

entry - the return value of getLockEntry(long)

isHeldByCurrentThread

public boolean isHeldByCurrentThread(long id)

Test whether the given id is already locked by the current thread.

waitForWaiters

public void waitForWaiters(long id,
                           int numWaiters)
                    throws InterruptedException

抛出:

InterruptedException