jdk/src/share/classes/java/security/PrivilegedAction.java

/*
 * Copyright 1998-2004 Sun Microsystems, Inc.  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.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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 */

package java.security;


/**
 * A computation to be performed with privileges enabled.  The computation is
 * performed by invoking <code>AccessController.doPrivileged</code> on the
 * <code>PrivilegedAction</code> object.  This interface is used only for
 * computations that do not throw checked exceptions; computations that
 * throw checked exceptions must use <code>PrivilegedExceptionAction</code>
 * instead.
 *
 * @see AccessController
 * @see AccessController#doPrivileged(PrivilegedAction)
 * @see PrivilegedExceptionAction
 */

public interface PrivilegedAction<T> {
    /**
     * Performs the computation.  This method will be called by
     * <code>AccessController.doPrivileged</code> after enabling privileges.
     *
     * @return a class-dependent value that may represent the results of the
     *         computation. Each class that implements
     *         <code>PrivilegedAction</code>
     *         should document what (if anything) this value represents.
     * @see AccessController#doPrivileged(PrivilegedAction)
     * @see AccessController#doPrivileged(PrivilegedAction,
     *                                     AccessControlContext)
     */
    T run();
}