1 /*
   2  * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 import java.io.Closeable;
  25 import java.io.IOException;
  26 
  27 /**
  28  * Implemented by closeable objects which might be able to report
  29  * an error when closed due to exceptional conditions.
  30  */
  31 public interface ExceptionallyCloseable extends Closeable {
  32 
  33     /**
  34      * Called when an instance of {@code ExceptionallyCloseable} is closed
  35      * due to some exceptional condition revealed by {@code cause}.
  36      *
  37      * @implSpec The default implementation of this method simply calls
  38      *           {@link #close()}. Implementation of this interface are
  39      *           suppose to override this method in order to ensure that
  40      *           the cause is properly reported.
  41      *
  42      * @param cause The reason for which the object is closed.
  43      * @throws IOException if {@link #close()} fails.
  44      */
  45     public default void closeExceptionally(Throwable cause) throws IOException {
  46         close();
  47     }
  48 
  49     public static void close(Throwable t, Closeable c) throws IOException {
  50         if (c instanceof ExceptionallyCloseable) {
  51             ((ExceptionallyCloseable)c).closeExceptionally(t);
  52         } else {
  53             c.close();
  54         }
  55     }
  56 }