com.hazelcast.spi.impl

Class AbstractCompletableFuture<V>

java.lang.Object

com.hazelcast.spi.impl.AbstractCompletableFuture<V>

Type Parameters:

V - The result type returned by this Future's get method

All Implemented Interfaces:

ICompletableFuture<V>, Future<V>

Direct Known Subclasses:

ChainingFuture, CompletableFutureTask, SimpleCompletableFuture, TrackableJobFuture

public abstract class AbstractCompletableFuture<V>
extends Object
implements ICompletableFuture<V>

A base ICompletableFuture implementation that may be explicitly completed by setting its value through setResult. Implements the logic of cancellation and callbacks execution.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractCompletableFuture(Executor defaultExecutor, ILogger logger)
protected	AbstractCompletableFuture(NodeEngine nodeEngine, ILogger logger)

Method Summary

Modifier and Type	Method and Description
void	andThen(ExecutionCallback<V> callback) Registers a callback that will run after this future is completed.
void	andThen(ExecutionCallback<V> callback, Executor executor) Registers a callback that will run with the provided executor after this future is completed.
boolean	cancel(boolean mayInterruptIfRunning)
protected void	cancelled(boolean mayInterruptIfRunning) Protected method invoked when this task transitions to state isCancelled.
protected void	done() Protected method invoked when this task transitions to state isDone (only normally - in case of cancellation cancelled() is invoked) The default implementation does nothing.
V	get()
V	get(long timeout, TimeUnit unit) PLEASE NOTE: It's legal to override this method, but please bear in mind that you should call super.get() or implement the done() and cancelled() callbacks to be notified if this future gets done or cancelled.
protected V	getResult() Returns: null - if cancelled or not done result - if done and result is NOT Throwable sneaky throws an exception - if done and result is Throwable
boolean	isCancelled()
boolean	isDone()
protected boolean	setResult(Object result) Sets the result.
protected boolean	shouldCancel(boolean mayInterruptIfRunning) Protected method invoked on cancel().

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractCompletableFuture

protected AbstractCompletableFuture(NodeEngine nodeEngine,
                                    ILogger logger)

AbstractCompletableFuture

protected AbstractCompletableFuture(Executor defaultExecutor,
                                    ILogger logger)

Method Detail

andThen

public void andThen(ExecutionCallback<V> callback)

Description copied from interface: ICompletableFuture

Registers a callback that will run after this future is completed. If this future is already completed, it runs immediately.

Please note that there is no ordering guarantee for running multiple callbacks. It is also not guaranteed that the callback will run within the same thread that completes the future.

Specified by:

andThen in interface ICompletableFuture<V>

Parameters:

callback - the callback to execute

andThen

public void andThen(ExecutionCallback<V> callback,
                    Executor executor)

Description copied from interface: ICompletableFuture

Registers a callback that will run with the provided executor after this future is completed. If this future is already completed, it runs immediately. The callback is called using the given executor. Please note that there is no ordering guarantee for executing multiple callbacks.

Specified by:

andThen in interface ICompletableFuture<V>

Parameters:

callback - the callback to execute

executor - the executor in which the callback will be run

isDone

public boolean isDone()

Specified by:

isDone in interface Future<V>

cancel

public final boolean cancel(boolean mayInterruptIfRunning)

Specified by:

cancel in interface Future<V>

shouldCancel

protected boolean shouldCancel(boolean mayInterruptIfRunning)

Protected method invoked on cancel(). Enables aborting the cancellation. Useful for futures' encompassing logic that can forbid the cancellation. By default always returns true.

Parameters:

mayInterruptIfRunning - passed through from cancel call

Returns:

true should the cancellation proceed; false otherwise

cancelled

protected void cancelled(boolean mayInterruptIfRunning)

Protected method invoked when this task transitions to state isCancelled. The default implementation does nothing. Subclasses may override this method to invoke callbacks or perform bookkeeping. Implementation has to handle exceptions itself.

Parameters:

mayInterruptIfRunning - true if the thread executing this task was supposed to be interrupted; otherwise, in-progress tasks are allowed to complete

isCancelled

public boolean isCancelled()

Specified by:

isCancelled in interface Future<V>

get

public final V get()
            throws InterruptedException,
                   ExecutionException

Specified by:

get in interface Future<V>

Throws:

InterruptedException

ExecutionException

get

public V get(long timeout,
             TimeUnit unit)
      throws ExecutionException,
             InterruptedException,
             TimeoutException

PLEASE NOTE: It's legal to override this method, but please bear in mind that you should call super.get() or implement the done() and cancelled() callbacks to be notified if this future gets done or cancelled. Otherwise the overridden implementation of get() may get stuck on waiting forever.

Specified by:

get in interface Future<V>

Throws:

ExecutionException

InterruptedException

TimeoutException

setResult

protected boolean setResult(Object result)

Sets the result. If result is an instance of Throwable, this future will be completed exceptionally. That is, get() will throw the exception rather than return it.

Returns:

true, if this call made this future to complete

done

protected void done()

Protected method invoked when this task transitions to state isDone (only normally - in case of cancellation cancelled() is invoked) The default implementation does nothing. Subclasses may override this method to invoke callbacks or perform bookkeeping. Implementation has to handle exceptions itself.

getResult

protected V getResult()

Returns:

• null - if cancelled or not done
• result - if done and result is NOT Throwable
• sneaky throws an exception - if done and result is Throwable