org.redisson

Class RedissonCountDownLatch

java.lang.Object

org.redisson.RedissonObject

org.redisson.RedissonCountDownLatch

All Implemented Interfaces:

RCountDownLatch, RCountDownLatchAsync, RObject, RObjectAsync

public class RedissonCountDownLatch
extends RedissonObject
implements RCountDownLatch

Distributed alternative to the CountDownLatch It has a advantage over CountDownLatch -- count can be reset via trySetCount(long).

Author:

Nikita Koksharov

Field Summary

Fields

Modifier and Type	Field and Description
static Long	newCountMessage
static Long	zeroCountMessage

Fields inherited from class org.redisson.RedissonObject

codec, commandExecutor

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	RedissonCountDownLatch(CommandAsyncExecutor commandExecutor, String name)

Method Summary

Modifier and Type	Method and Description
void	await() Causes the current thread to wait until the latch has counted down to zero, unless the thread is interrupted.
boolean	await(long time, TimeUnit unit) Causes the current thread to wait until the latch has counted down to zero, unless the thread is interrupted, or the specified waiting time elapses.
void	countDown() Decrements the count of the latch, releasing all waiting threads if the count reaches zero.
RFuture<Void>	countDownAsync() Decrements the count of the latch, releasing all waiting threads if the count reaches zero.
RFuture<Boolean>	deleteAsync() Delete object in async mode
long	getCount() Returns the current count.
RFuture<Long>	getCountAsync() Returns the current count.
boolean	trySetCount(long count) Sets new count value only if previous count already has reached zero or is not set at all.
RFuture<Boolean>	trySetCountAsync(long count) Sets new count value only if previous count already has reached zero or is not set at all.

Methods inherited from class org.redisson.RedissonObject

await, copy, copyAsync, delete, encode, encode, encode, encodeMapKey, encodeMapKeys, encodeMapValue, encodeMapValues, get, getCodec, getName, getName, isExists, isExistsAsync, migrate, migrateAsync, move, moveAsync, prefixName, rename, renameAsync, renamenx, renamenxAsync, suffixName, toSeconds, touch, touchAsync, unlink, unlinkAsync

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.redisson.api.RObject

copy, delete, getCodec, getName, isExists, migrate, move, rename, renamenx, touch, unlink

Methods inherited from interface org.redisson.api.RObjectAsync

copyAsync, isExistsAsync, migrateAsync, moveAsync, renameAsync, renamenxAsync, touchAsync, unlinkAsync

Field Detail

zeroCountMessage

public static final Long zeroCountMessage

newCountMessage

public static final Long newCountMessage

Constructor Detail

RedissonCountDownLatch

protected RedissonCountDownLatch(CommandAsyncExecutor commandExecutor,
                                 String name)

Method Detail

await

public void await()
           throws InterruptedException

Description copied from interface: RCountDownLatch

Causes the current thread to wait until the latch has counted down to zero, unless the thread is interrupted.

If the current count is zero then this method returns immediately.

If the current count is greater than zero then the current thread becomes disabled for thread scheduling purposes and lies dormant until one of two things happen:

• The count reaches zero due to invocations of the RCountDownLatch.countDown() method; or
• Some other thread interrupts the current thread.

If the current thread:

• has its interrupted status set on entry to this method; or
• is interrupted while waiting,

then InterruptedException is thrown and the current thread's interrupted status is cleared.

Specified by:

await in interface RCountDownLatch

Throws:

InterruptedException - if the current thread is interrupted while waiting

await

public boolean await(long time,
                     TimeUnit unit)
              throws InterruptedException

Description copied from interface: RCountDownLatch

Causes the current thread to wait until the latch has counted down to zero, unless the thread is interrupted, or the specified waiting time elapses.

If the current count is zero then this method returns immediately with the value true.

If the current count is greater than zero then the current thread becomes disabled for thread scheduling purposes and lies dormant until one of three things happen:

• The count reaches zero due to invocations of the RCountDownLatch.countDown() method; or
• Some other thread interrupts the current thread; or
• The specified waiting time elapses.

If the count reaches zero then the method returns with the value true.

If the current thread:

• has its interrupted status set on entry to this method; or
• is interrupted while waiting,

then InterruptedException is thrown and the current thread's interrupted status is cleared.

If the specified waiting time elapses then the value false is returned. If the time is less than or equal to zero, the method will not wait at all.

Specified by:

await in interface RCountDownLatch

Parameters:

time - the maximum time to wait

unit - the time unit of the timeout argument

Returns:

true if the count reached zero and false if the waiting time elapsed before the count reached zero

Throws:

InterruptedException - if the current thread is interrupted while waiting

countDown

public void countDown()

Description copied from interface: RCountDownLatch

Decrements the count of the latch, releasing all waiting threads if the count reaches zero.

If the current count is greater than zero then it is decremented. If the new count is zero then all waiting threads are re-enabled for thread scheduling purposes.

If the current count equals zero then nothing happens.

Specified by:

countDown in interface RCountDownLatch

countDownAsync

public RFuture<Void> countDownAsync()

Description copied from interface: RCountDownLatchAsync

Decrements the count of the latch, releasing all waiting threads if the count reaches zero.

If the current count is greater than zero then it is decremented. If the new count is zero then all waiting threads are re-enabled for thread scheduling purposes.

If the current count equals zero then nothing happens.

Specified by:

countDownAsync in interface RCountDownLatchAsync

Returns:

void

getCount

public long getCount()

Description copied from interface: RCountDownLatch

Returns the current count.

This method is typically used for debugging and testing purposes.

Specified by:

getCount in interface RCountDownLatch

Returns:

the current count

getCountAsync

public RFuture<Long> getCountAsync()

Description copied from interface: RCountDownLatchAsync

Returns the current count.

This method is typically used for debugging and testing purposes.

Specified by:

getCountAsync in interface RCountDownLatchAsync

Returns:

the current count

trySetCount

public boolean trySetCount(long count)

Description copied from interface: RCountDownLatch

Sets new count value only if previous count already has reached zero or is not set at all.

Specified by:

trySetCount in interface RCountDownLatch

Parameters:

count - - number of times RCountDownLatch.countDown() must be invoked before threads can pass through RCountDownLatch.await()

Returns:

true if new count setted false if previous count has not reached zero

trySetCountAsync

public RFuture<Boolean> trySetCountAsync(long count)

Description copied from interface: RCountDownLatchAsync

Sets new count value only if previous count already has reached zero or is not set at all.

Specified by:

trySetCountAsync in interface RCountDownLatchAsync

Parameters:

count - - number of times countDown must be invoked before threads can pass through await

Returns:

true if new count setted false if previous count has not reached zero

deleteAsync

public RFuture<Boolean> deleteAsync()

Description copied from interface: RObjectAsync

Delete object in async mode

Specified by:

deleteAsync in interface RObjectAsync

Overrides:

deleteAsync in class RedissonObject

Returns:

true if object was deleted false if not