View Javadoc
1   /*
2    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3    *
4    * This code is free software; you can redistribute it and/or modify it
5    * under the terms of the GNU General Public License version 2 only, as
6    * published by the Free Software Foundation.  Oracle designates this
7    * particular file as subject to the "Classpath" exception as provided
8    * by Oracle in the LICENSE file that accompanied this code.
9    *
10   * This code is distributed in the hope that it will be useful, but WITHOUT
11   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13   * version 2 for more details (a copy is included in the LICENSE file that
14   * accompanied this code).
15   *
16   * You should have received a copy of the GNU General Public License version
17   * 2 along with this work; if not, write to the Free Software Foundation,
18   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19   *
20   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21   * or visit www.oracle.com if you need additional information or have any
22   * questions.
23   */
24  
25  /*
26   * This file is available under and governed by the GNU General Public
27   * License version 2 only, as published by the Free Software Foundation.
28   * However, the following notice accompanied the original version of this
29   * file:
30   *
31   * Written by Doug Lea with assistance from members of JCP JSR-166
32   * Expert Group and released to the public domain, as explained at
33   * http://creativecommons.org/publicdomain/zero/1.0/
34   */
35  
36  package java.util.concurrent;
37  
38  /**
39   * A handler for tasks that cannot be executed by a {@link ThreadPoolExecutor}.
40   *
41   * @since 1.5
42   * @author Doug Lea
43   */
44  public interface RejectedExecutionHandler {
45  
46      /**
47       * Method that may be invoked by a {@link ThreadPoolExecutor} when
48       * {@link ThreadPoolExecutor#execute execute} cannot accept a
49       * task.  This may occur when no more threads or queue slots are
50       * available because their bounds would be exceeded, or upon
51       * shutdown of the Executor.
52       *
53       * <p>In the absence of other alternatives, the method may throw
54       * an unchecked {@link RejectedExecutionException}, which will be
55       * propagated to the caller of {@code execute}.
56       *
57       * @param r the runnable task requested to be executed
58       * @param executor the executor attempting to execute this task
59       * @throws RejectedExecutionException if there is no remedy
60       */
61      void rejectedExecution(Runnable r, ThreadPoolExecutor executor);
62  }