Java tutorial
/* * Copyright (c) 1998, 2018, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.security; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.ObjectStreamField; import jdk.internal.access.SharedSecrets; /** * This exception is thrown by * {@code doPrivileged(PrivilegedExceptionAction)} and * {@code doPrivileged(PrivilegedExceptionAction, * AccessControlContext context)} to indicate * that the action being performed threw a checked exception. The exception * thrown by the action can be obtained by calling the * {@code getException} method. In effect, an * {@code PrivilegedActionException} is a "wrapper" * for an exception thrown by a privileged action. * * <p>As of release 1.4, this exception has been retrofitted to conform to * the general purpose exception-chaining mechanism. The "exception thrown * by the privileged computation" that is provided at construction time and * accessed via the {@link #getException()} method is now known as the * <i>cause</i>, and may be accessed via the {@link Throwable#getCause()} * method, as well as the aforementioned "legacy method." * * @since 1.2 * @see PrivilegedExceptionAction * @see AccessController#doPrivileged(PrivilegedExceptionAction) * @see AccessController#doPrivileged(PrivilegedExceptionAction,AccessControlContext) */ public class PrivilegedActionException extends Exception { // use serialVersionUID from JDK 1.2.2 for interoperability private static final long serialVersionUID = 4724086851538908602L; /** * Constructs a new PrivilegedActionException "wrapping" * the specific Exception. * * @param exception The exception thrown */ public PrivilegedActionException(Exception exception) { super(null, exception); // Disallow initCause } /** * Returns the exception thrown by the privileged computation that * resulted in this {@code PrivilegedActionException}. * * <p>This method predates the general-purpose exception chaining facility. * The {@link Throwable#getCause()} method is now the preferred means of * obtaining this information. * * @return the exception thrown by the privileged computation that * resulted in this {@code PrivilegedActionException}. * @see PrivilegedExceptionAction * @see AccessController#doPrivileged(PrivilegedExceptionAction) * @see AccessController#doPrivileged(PrivilegedExceptionAction, * AccessControlContext) */ public Exception getException() { return (Exception) super.getCause(); } public String toString() { String s = getClass().getName(); Throwable cause = super.getCause(); return (cause != null) ? (s + ": " + cause.toString()) : s; } /** * Serializable fields for UndeclaredThrowableException. * * @serialField undeclaredThrowable Throwable */ private static final ObjectStreamField[] serialPersistentFields = { new ObjectStreamField("exception", Exception.class) }; /* * Reconstitutes the PrivilegedActionException instance from a stream * and initialize the cause properly when deserializing from an older * version. * * The getException and getCause method returns the private "exception" * field in the older implementation and PrivilegedActionException::cause * was set to null. */ private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException { ObjectInputStream.GetField fields = s.readFields(); Exception exception = (Exception) fields.get("exception", null); if (exception != null) { SharedSecrets.getJavaLangAccess().setCause(this, exception); } } /* * To maintain compatibility with older implementation, write a serial * "exception" field with the cause as the value. */ private void writeObject(ObjectOutputStream out) throws IOException { ObjectOutputStream.PutField fields = out.putFields(); fields.put("exception", super.getCause()); out.writeFields(); } }