1 /*
   2  * Copyright (c) 1998, 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.security;
  27 
  28 
  29 /**
  30  * A computation to be performed with privileges enabled.  The computation is
  31  * performed by invoking {@code AccessController.doPrivileged} on the
  32  * {@code PrivilegedAction} object.  This interface is used only for
  33  * computations that do not throw checked exceptions; computations that
  34  * throw checked exceptions must use {@code PrivilegedExceptionAction}
  35  * instead.
  36  *
  37  * @see AccessController
  38  * @see AccessController#doPrivileged(PrivilegedAction)
  39  * @see PrivilegedExceptionAction
  40  */
  41 
  42 public interface PrivilegedAction<T> {
  43     /**
  44      * Performs the computation.  This method will be called by
  45      * {@code AccessController.doPrivileged} after enabling privileges.
  46      *
  47      * @return a class-dependent value that may represent the results of the
  48      *         computation. Each class that implements
  49      *         {@code PrivilegedAction}
  50      *         should document what (if anything) this value represents.
  51      * @see AccessController#doPrivileged(PrivilegedAction)
  52      * @see AccessController#doPrivileged(PrivilegedAction,
  53      *                                     AccessControlContext)
  54      */
  55     T run();
  56 }