1 /*
   2  * Copyright (c) 2009, 2010, 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package java.lang;
  27 
  28 /**
  29  * A resource that must be closed when it is no longer needed.
  30  *
  31  * @author Josh Bloch
  32  * @since 1.7
  33  */
  34 public interface AutoCloseable {
  35     /**
  36      * Close this resource, relinquishing any underlying resources.
  37      * This method is invoked automatically by the automatic resource
  38      * management block construct.
  39      *
  40      * <p>Classes implementing this method are strongly encouraged to
  41      * be declared to throw more specific exceptions (or no exception
  42      * at all, if the close cannot fail).
  43      *
  44      * <p>Note that unlike the {@link java.io.Closeable#close close}
  45      * method of {@link java.io.Closeable}, this {@code close} method
  46      * is <em>not</em> required to be idempotent.  In other words,
  47      * calling this {@code close} method more than once may have some
  48      * visible side effect, unlike {@code Closeable.close} which is
  49      * required to have no effect if called more than once.
  50      *
  51      * @throws Exception if this resource cannot be closed
  52      */
  53     void close() throws Exception;
  54 }