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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain. Use, modify, and |
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* redistribute this code in any way without acknowledgement. |
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*/ |
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|
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package java.util.concurrent; |
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|
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/** |
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* Something (usually a task) that can be cancelled. Cancellation is |
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* performed by the <tt>cancel</tt> method. Additional methods are |
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* provided to determine if the task completed normally or was |
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* cancelled. |
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* |
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* @since 1.5 |
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* |
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* @spec JSR-166 |
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* @revised $Date: 2003/06/07 19:54:10 $ |
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* @editor $Author: jozart $ |
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*/ |
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public interface Cancellable { |
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|
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/** |
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* Attempts to cancel execution of this task. This attempt will |
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* fail if the task has already completed or could not be |
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* cancelled for some other reason. If successful, and this task |
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* has not started when <tt>cancel</tt> is called, this task will |
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* never run. If the task has already started, then the |
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* <tt>interruptIfRunning</tt> parameter determines whether the |
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* thread executing this task should be interrupted in an attempt |
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* to stop the task. |
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* |
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* @param mayInterruptIfRunning <tt>true</tt> if the thread executing this |
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* task should be interrupted; otherwise, in-progress tasks are allowed |
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* to complete |
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* @return <tt>false</tt> if the task could not be cancelled, |
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* typically because is has already completed normally; |
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* <tt>true</tt> otherwise |
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*/ |
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boolean cancel(boolean mayInterruptIfRunning); |
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|
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/** |
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* Returns <tt>true</tt> if this task was cancelled before it completed |
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* normally. |
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* |
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* @return <tt>true</tt> if task was cancelled before it completed |
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*/ |
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boolean isCancelled(); |
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|
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/** |
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* Returns <tt>true</tt> if this task ran to completion or was cancelled. |
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* |
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* @return <tt>true</tt> if task completed normally or was cancelled |
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*/ |
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boolean isDone(); |
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} |
