com.fr.third.jgroups.util

类 Promise<T>

java.lang.Object

com.fr.third.jgroups.util.Promise<T>

public class Promise<T>
extends java.lang.Object

Allows a thread to submit an asynchronous request and to wait for the result. The caller may choose to check for the result at a later time, or immediately and it may block or not. Both the caller and responder have to know the promise.

When the result is available, hasResult() will always return true and getResult() will return the same result. In order to block for a different result, reset() has to be called first.

作者:

Bela Ban

构造器概要

构造器

构造器和说明
Promise()

方法概要

方法

限定符和类型	方法和说明
protected T	_getResultWithTimeout(long timeout) Blocks until a result is available, or timeout milliseconds have elapsed.
java.util.concurrent.locks.Condition	getCond()
java.util.concurrent.locks.Lock	getLock()
T	getResult()
T	getResult(long timeout) Returns the result, but never throws a TimeoutException; returns null instead.
T	getResult(long timeout, boolean reset)
T	getResultWithTimeout(long timeout) Blocks until a result is available, or timeout milliseconds have elapsed
T	getResultWithTimeout(long timeout, boolean reset)
boolean	hasResult() Checks whether result is available.
void	reset() Causes all waiting threads to return
void	setResult(T obj) Sets the result and notifies any threads waiting for it
java.lang.String	toString()

从类继承的方法 java.lang.Object

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

构造器详细资料

Promise

public Promise()

方法详细资料

getLock

public java.util.concurrent.locks.Lock getLock()

getCond

public java.util.concurrent.locks.Condition getCond()

getResultWithTimeout

public T getResultWithTimeout(long timeout)
                       throws TimeoutException

Blocks until a result is available, or timeout milliseconds have elapsed

参数:

timeout - in ms

返回:

An object

抛出:

TimeoutException - If a timeout occurred (implies that timeout > 0)

getResultWithTimeout

public T getResultWithTimeout(long timeout,
                     boolean reset)
                       throws TimeoutException

抛出:

TimeoutException

getResult

public T getResult()

getResult

public T getResult(long timeout)

Returns the result, but never throws a TimeoutException; returns null instead.

参数:

timeout - in ms

返回:

T

getResult

public T getResult(long timeout,
          boolean reset)

hasResult

public boolean hasResult()

Checks whether result is available. Does not block.

setResult

public void setResult(T obj)

Sets the result and notifies any threads waiting for it

reset

public void reset()

Causes all waiting threads to return

toString

public java.lang.String toString()

覆盖:

toString 在类中 java.lang.Object

_getResultWithTimeout

protected T _getResultWithTimeout(long timeout)
                           throws TimeoutException

Blocks until a result is available, or timeout milliseconds have elapsed. Needs to be called with lock held

参数:

timeout - in ms

返回:

An object

抛出:

TimeoutException - If a timeout occurred (implies that timeout > 0)