com.aspc.remote.util.misc

Class SyncBlock

java.lang.Object

com.aspc.remote.util.misc.SyncBlock

public class SyncBlock
extends java.lang.Object

A synchronized block replacement to prevent deadlocks When you call the method take() on a SyncBlock object you'll block up until the specified maximum number of seconds and then an error will be thrown if you are unable to obtain the lock on this object. You must ALWAYS call release() on any sync SyncBlock that you have obtained the lock on. The SyncBlock differs from the keyword synchronized in that it is interruptible and that it will timeout if it blocks for too long. The SyncBlock enhances a normal java.lang.concurrent.Lock in that it will interrupt the blocking thread if it holds the lock for too long and if the thread holding the lock is not alive a new lock object will be created and a fatal email will be generated with the details. If a lock fails to be obtained ( which would have been a deadlock) a fatal email will be generated with the details of the two threads and the blocking thread will be interrupted and the calling thread will have an error thrown.

SyncBlock a replacement for the synchronised keyword

THREAD MODE: MULTI-THREADED

Since:

29 September 2008

Author:

Nigel Leck

Constructor Summary

Constructors

Constructor and Description
SyncBlock(java.lang.String name) A synchronized block
SyncBlock(java.lang.String name, int seconds) A synchronized block

Method Summary

Modifier and Type	Method and Description
static long	errorCount() The error count
void	release() release the lock
void	take() take the lock and throw an error if you can't get it.
java.lang.String	toString() The name of this SyncBlock
boolean	tryLock() try to get the lock
boolean	tryLock(int seconds) Try for a few seconds to get the lock

Methods inherited from class java.lang.Object

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

Constructor Detail

SyncBlock

public SyncBlock(java.lang.String name)

A synchronized block

Parameters:

name - the name of the block

SyncBlock

public SyncBlock(java.lang.String name,
                 int seconds)

A synchronized block

Parameters:

name - the name of the block

seconds - the seconds

Method Detail

errorCount

public static long errorCount()

The error count

Returns:

the count

toString

@CheckReturnValue
 @Nonnull
public java.lang.String toString()

The name of this SyncBlock

Overrides:

toString in class java.lang.Object

Returns:

the name of the block.

release

public void release()

release the lock

tryLock

public boolean tryLock()

try to get the lock

Returns:

true if we got the lock

tryLock

public boolean tryLock(int seconds)
                throws java.lang.InterruptedException

Try for a few seconds to get the lock

Parameters:

seconds - the number of seconds

Returns:

true if we got the lock

Throws:

java.lang.InterruptedException - interrupted.

take

public void take()

take the lock and throw an error if you can't get it.