1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/rt/emul/compact/src/main/java/java/util/concurrent/ScheduledExecutorService.java Sat Mar 19 10:46:31 2016 +0100
1.3 @@ -0,0 +1,187 @@
1.4 +/*
1.5 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.6 + *
1.7 + * This code is free software; you can redistribute it and/or modify it
1.8 + * under the terms of the GNU General Public License version 2 only, as
1.9 + * published by the Free Software Foundation. Oracle designates this
1.10 + * particular file as subject to the "Classpath" exception as provided
1.11 + * by Oracle in the LICENSE file that accompanied this code.
1.12 + *
1.13 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.14 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.15 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.16 + * version 2 for more details (a copy is included in the LICENSE file that
1.17 + * accompanied this code).
1.18 + *
1.19 + * You should have received a copy of the GNU General Public License version
1.20 + * 2 along with this work; if not, write to the Free Software Foundation,
1.21 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.22 + *
1.23 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.24 + * or visit www.oracle.com if you need additional information or have any
1.25 + * questions.
1.26 + */
1.27 +
1.28 +/*
1.29 + * This file is available under and governed by the GNU General Public
1.30 + * License version 2 only, as published by the Free Software Foundation.
1.31 + * However, the following notice accompanied the original version of this
1.32 + * file:
1.33 + *
1.34 + * Written by Doug Lea with assistance from members of JCP JSR-166
1.35 + * Expert Group and released to the public domain, as explained at
1.36 + * http://creativecommons.org/publicdomain/zero/1.0/
1.37 + */
1.38 +
1.39 +package java.util.concurrent;
1.40 +import java.util.concurrent.atomic.*;
1.41 +import java.util.*;
1.42 +
1.43 +/**
1.44 + * An {@link ExecutorService} that can schedule commands to run after a given
1.45 + * delay, or to execute periodically.
1.46 + *
1.47 + * <p> The <tt>schedule</tt> methods create tasks with various delays
1.48 + * and return a task object that can be used to cancel or check
1.49 + * execution. The <tt>scheduleAtFixedRate</tt> and
1.50 + * <tt>scheduleWithFixedDelay</tt> methods create and execute tasks
1.51 + * that run periodically until cancelled.
1.52 + *
1.53 + * <p> Commands submitted using the {@link Executor#execute} and
1.54 + * {@link ExecutorService} <tt>submit</tt> methods are scheduled with
1.55 + * a requested delay of zero. Zero and negative delays (but not
1.56 + * periods) are also allowed in <tt>schedule</tt> methods, and are
1.57 + * treated as requests for immediate execution.
1.58 + *
1.59 + * <p>All <tt>schedule</tt> methods accept <em>relative</em> delays and
1.60 + * periods as arguments, not absolute times or dates. It is a simple
1.61 + * matter to transform an absolute time represented as a {@link
1.62 + * java.util.Date} to the required form. For example, to schedule at
1.63 + * a certain future <tt>date</tt>, you can use: <tt>schedule(task,
1.64 + * date.getTime() - System.currentTimeMillis(),
1.65 + * TimeUnit.MILLISECONDS)</tt>. Beware however that expiration of a
1.66 + * relative delay need not coincide with the current <tt>Date</tt> at
1.67 + * which the task is enabled due to network time synchronization
1.68 + * protocols, clock drift, or other factors.
1.69 + *
1.70 + * The {@link Executors} class provides convenient factory methods for
1.71 + * the ScheduledExecutorService implementations provided in this package.
1.72 + *
1.73 + * <h3>Usage Example</h3>
1.74 + *
1.75 + * Here is a class with a method that sets up a ScheduledExecutorService
1.76 + * to beep every ten seconds for an hour:
1.77 + *
1.78 + * <pre> {@code
1.79 + * import static java.util.concurrent.TimeUnit.*;
1.80 + * class BeeperControl {
1.81 + * private final ScheduledExecutorService scheduler =
1.82 + * Executors.newScheduledThreadPool(1);
1.83 + *
1.84 + * public void beepForAnHour() {
1.85 + * final Runnable beeper = new Runnable() {
1.86 + * public void run() { System.out.println("beep"); }
1.87 + * };
1.88 + * final ScheduledFuture<?> beeperHandle =
1.89 + * scheduler.scheduleAtFixedRate(beeper, 10, 10, SECONDS);
1.90 + * scheduler.schedule(new Runnable() {
1.91 + * public void run() { beeperHandle.cancel(true); }
1.92 + * }, 60 * 60, SECONDS);
1.93 + * }
1.94 + * }}</pre>
1.95 + *
1.96 + * @since 1.5
1.97 + * @author Doug Lea
1.98 + */
1.99 +public interface ScheduledExecutorService extends ExecutorService {
1.100 +
1.101 + /**
1.102 + * Creates and executes a one-shot action that becomes enabled
1.103 + * after the given delay.
1.104 + *
1.105 + * @param command the task to execute
1.106 + * @param delay the time from now to delay execution
1.107 + * @param unit the time unit of the delay parameter
1.108 + * @return a ScheduledFuture representing pending completion of
1.109 + * the task and whose <tt>get()</tt> method will return
1.110 + * <tt>null</tt> upon completion
1.111 + * @throws RejectedExecutionException if the task cannot be
1.112 + * scheduled for execution
1.113 + * @throws NullPointerException if command is null
1.114 + */
1.115 + public ScheduledFuture<?> schedule(Runnable command,
1.116 + long delay, TimeUnit unit);
1.117 +
1.118 + /**
1.119 + * Creates and executes a ScheduledFuture that becomes enabled after the
1.120 + * given delay.
1.121 + *
1.122 + * @param callable the function to execute
1.123 + * @param delay the time from now to delay execution
1.124 + * @param unit the time unit of the delay parameter
1.125 + * @return a ScheduledFuture that can be used to extract result or cancel
1.126 + * @throws RejectedExecutionException if the task cannot be
1.127 + * scheduled for execution
1.128 + * @throws NullPointerException if callable is null
1.129 + */
1.130 + public <V> ScheduledFuture<V> schedule(Callable<V> callable,
1.131 + long delay, TimeUnit unit);
1.132 +
1.133 + /**
1.134 + * Creates and executes a periodic action that becomes enabled first
1.135 + * after the given initial delay, and subsequently with the given
1.136 + * period; that is executions will commence after
1.137 + * <tt>initialDelay</tt> then <tt>initialDelay+period</tt>, then
1.138 + * <tt>initialDelay + 2 * period</tt>, and so on.
1.139 + * If any execution of the task
1.140 + * encounters an exception, subsequent executions are suppressed.
1.141 + * Otherwise, the task will only terminate via cancellation or
1.142 + * termination of the executor. If any execution of this task
1.143 + * takes longer than its period, then subsequent executions
1.144 + * may start late, but will not concurrently execute.
1.145 + *
1.146 + * @param command the task to execute
1.147 + * @param initialDelay the time to delay first execution
1.148 + * @param period the period between successive executions
1.149 + * @param unit the time unit of the initialDelay and period parameters
1.150 + * @return a ScheduledFuture representing pending completion of
1.151 + * the task, and whose <tt>get()</tt> method will throw an
1.152 + * exception upon cancellation
1.153 + * @throws RejectedExecutionException if the task cannot be
1.154 + * scheduled for execution
1.155 + * @throws NullPointerException if command is null
1.156 + * @throws IllegalArgumentException if period less than or equal to zero
1.157 + */
1.158 + public ScheduledFuture<?> scheduleAtFixedRate(Runnable command,
1.159 + long initialDelay,
1.160 + long period,
1.161 + TimeUnit unit);
1.162 +
1.163 + /**
1.164 + * Creates and executes a periodic action that becomes enabled first
1.165 + * after the given initial delay, and subsequently with the
1.166 + * given delay between the termination of one execution and the
1.167 + * commencement of the next. If any execution of the task
1.168 + * encounters an exception, subsequent executions are suppressed.
1.169 + * Otherwise, the task will only terminate via cancellation or
1.170 + * termination of the executor.
1.171 + *
1.172 + * @param command the task to execute
1.173 + * @param initialDelay the time to delay first execution
1.174 + * @param delay the delay between the termination of one
1.175 + * execution and the commencement of the next
1.176 + * @param unit the time unit of the initialDelay and delay parameters
1.177 + * @return a ScheduledFuture representing pending completion of
1.178 + * the task, and whose <tt>get()</tt> method will throw an
1.179 + * exception upon cancellation
1.180 + * @throws RejectedExecutionException if the task cannot be
1.181 + * scheduled for execution
1.182 + * @throws NullPointerException if command is null
1.183 + * @throws IllegalArgumentException if delay less than or equal to zero
1.184 + */
1.185 + public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command,
1.186 + long initialDelay,
1.187 + long delay,
1.188 + TimeUnit unit);
1.189 +
1.190 +}