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 import jdk.internal.misc.SharedSecrets;
  29 
  30 import java.io.IOException;
  31 import java.io.ObjectInputStream;
  32 import java.io.ObjectOutputStream;
  33 import java.io.ObjectStreamField;
  34 
  35 /**
  36  * This exception is thrown by
  37  * {@code doPrivileged(PrivilegedExceptionAction)} and
  38  * {@code doPrivileged(PrivilegedExceptionAction,
  39  * AccessControlContext context)} to indicate
  40  * that the action being performed threw a checked exception.  The exception
  41  * thrown by the action can be obtained by calling the
  42  * {@code getException} method.  In effect, an
  43  * {@code PrivilegedActionException} is a "wrapper"
  44  * for an exception thrown by a privileged action.
  45  *
  46  * <p>As of release 1.4, this exception has been retrofitted to conform to
  47  * the general purpose exception-chaining mechanism.  The "exception thrown
  48  * by the privileged computation" that is provided at construction time and
  49  * accessed via the {@link #getException()} method is now known as the
  50  * <i>cause</i>, and may be accessed via the {@link Throwable#getCause()}
  51  * method, as well as the aforementioned "legacy method."
  52  *
  53  * @since 1.2
  54  * @see PrivilegedExceptionAction
  55  * @see AccessController#doPrivileged(PrivilegedExceptionAction)
  56  * @see AccessController#doPrivileged(PrivilegedExceptionAction,AccessControlContext)
  57  */
  58 public class PrivilegedActionException extends Exception {
  59     // use serialVersionUID from JDK 1.2.2 for interoperability
  60     private static final long serialVersionUID = 4724086851538908602L;
  61 
  62     /**
  63      * Constructs a new PrivilegedActionException &quot;wrapping&quot;
  64      * the specific Exception.
  65      *
  66      * @param exception The exception thrown
  67      */
  68     public PrivilegedActionException(Exception exception) {
  69         super(null, exception);  // Disallow initCause
  70     }
  71 
  72     /**
  73      * Returns the exception thrown by the privileged computation that
  74      * resulted in this {@code PrivilegedActionException}.
  75      *
  76      * <p>This method predates the general-purpose exception chaining facility.
  77      * The {@link Throwable#getCause()} method is now the preferred means of
  78      * obtaining this information.
  79      *
  80      * @return the exception thrown by the privileged computation that
  81      *         resulted in this {@code PrivilegedActionException}.
  82      * @see PrivilegedExceptionAction
  83      * @see AccessController#doPrivileged(PrivilegedExceptionAction)
  84      * @see AccessController#doPrivileged(PrivilegedExceptionAction,
  85      *                                            AccessControlContext)
  86      */
  87     public Exception getException() {
  88         return (Exception)super.getCause();
  89     }
  90 
  91     public String toString() {
  92         String s = getClass().getName();
  93         Throwable cause = super.getCause();
  94         return (cause != null) ? (s + ": " + cause.toString()) : s;
  95     }
  96 
  97 
  98     /**
  99      * Serializable fields for UndeclaredThrowableException.
 100      *
 101      * @serialField undeclaredThrowable Throwable
 102      */
 103     private static final ObjectStreamField[] serialPersistentFields = {
 104         new ObjectStreamField("exception", Exception.class)
 105     };
 106 
 107     /*
 108      * Reconstitutes the PrivilegedActionException instance from a stream
 109      * and initialize the cause properly when deserializing from an older
 110      * version.
 111      *
 112      * The getException and getCause method returns the private "exception"
 113      * field in the older implementation and PrivilegedActionException::cause
 114      * was set to null.
 115      */
 116     private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
 117         ObjectInputStream.GetField fields = s.readFields();
 118         Exception exception = (Exception) fields.get("exception", null);
 119         if (exception != null) {
 120             SharedSecrets.getJavaLangAccess().setCause(this, exception);
 121         }
 122     }
 123 
 124     /*
 125      * To maintain compatibility with older implementation, write a serial
 126      * "exception" field with the cause as the value.
 127      */
 128     private void writeObject(ObjectOutputStream out) throws IOException {
 129         ObjectOutputStream.PutField fields = out.putFields();
 130         fields.put("exception", super.getCause());
 131         out.writeFields();
 132     }
 133 }