Package org.apache.flink.core.testutils

Class BlockerSync

java.lang.Object

org.apache.flink.core.testutils.BlockerSync

public class BlockerSync
extends Object

A utility to help synchronize two threads in cases where one of them is supposed to reach a blocking state before the other may continue.

Use as follows:

 final BlockerSync sync = new BlockerSync();

 // thread to be blocked
 Runnable toBeBlocked = () -> {
     // do something, like acquire a shared resource
     sync.blockNonInterruptible();
     // release resource
 }

 new Thread(toBeBlocked).start();
 sync.awaitBlocker();

 // do stuff that requires the other thread to still hold the resource
 sync.releaseBlocker();
 

Constructor Summary

Constructors

Constructor	Description
BlockerSync()

Method Summary

Modifier and Type	Method	Description
void	awaitBlocker()	Waits until the blocking thread has entered the method block() or blockNonInterruptible().
void	block()	Blocks until releaseBlocker() is called or this thread is interrupted.
void	blockNonInterruptible()	Blocks until releaseBlocker() is called.
void	releaseBlocker()	Lets the blocked thread continue.

Methods inherited from class java.lang.Object

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

Constructor Details

BlockerSync

public BlockerSync()

Method Details

awaitBlocker

public void awaitBlocker()
                  throws InterruptedException

Waits until the blocking thread has entered the method block() or blockNonInterruptible().

Throws:

InterruptedException

block

public void block()
           throws InterruptedException

Blocks until releaseBlocker() is called or this thread is interrupted. Notifies the awaiting thread that waits in the method awaitBlocker().

Throws:

InterruptedException

blockNonInterruptible

public void blockNonInterruptible()

Blocks until releaseBlocker() is called. Notifies the awaiting thread that waits in the method awaitBlocker().

releaseBlocker

public void releaseBlocker()

Lets the blocked thread continue.