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 * 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

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 * questions.

 */

package java.security;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.io.ObjectStreamField;

/**

 * 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();

    }

}