1 /*
   2  * Copyright (c) 2009, 2011, 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      * Closes this resource, relinquishing any underlying resources.
  37      * This method is invoked automatically on objects managed by the
  38      * {@code try}-with-resources statement.
  39      *
  40      * <p>While this interface method is declared to throw {@code
  41      * Exception}, implementers are <em>strongly</em> encouraged to
  42      * declare concrete implementations of the {@code close} method to
  43      * throw more specific exceptions, or to throw no exception at all
  44      * if the close operation cannot fail.
  45      *
  46      * <p> Cases where the close operation may fail require careful
  47      * attention by implementers. It is strongly advised to relinquish
  48      * the underlying resources and to internally <em>mark</em> the
  49      * resource as closed, prior to throwing the exception. The {@code
  50      * close} method is unlikely to be invoked more than once and so
  51      * this ensures that the resources are released in a timely manner.
  52      * Furthermore it reduces problems that could arise when the resource
  53      * wraps, or is wrapped, by another resource.

   1 /*
   2  * Copyright (c) 2009, 2013, 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 @FunctionalInterface
  35 public interface AutoCloseable {
  36     /**
  37      * Closes this resource, relinquishing any underlying resources.
  38      * This method is invoked automatically on objects managed by the
  39      * {@code try}-with-resources statement.
  40      *
  41      * <p>While this interface method is declared to throw {@code
  42      * Exception}, implementers are <em>strongly</em> encouraged to
  43      * declare concrete implementations of the {@code close} method to
  44      * throw more specific exceptions, or to throw no exception at all
  45      * if the close operation cannot fail.
  46      *
  47      * <p> Cases where the close operation may fail require careful
  48      * attention by implementers. It is strongly advised to relinquish
  49      * the underlying resources and to internally <em>mark</em> the
  50      * resource as closed, prior to throwing the exception. The {@code
  51      * close} method is unlikely to be invoked more than once and so
  52      * this ensures that the resources are released in a timely manner.
  53      * Furthermore it reduces problems that could arise when the resource
  54      * wraps, or is wrapped, by another resource.