/*

 * Copyright (c) 1998, 2006, 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

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 */

package sun.security.action;

/**

 * A convenience class for retrieving the <code>Long</code> value of a system

 * property as a privileged action.

 *

 * <p>An instance of this class can be used as the argument of

 * <code>AccessController.doPrivileged</code>.

 *

 * <p>The following code retrieves the <code>Long</code> value of the system

 * property named <code>"prop"</code> as a privileged action. Since it does

 * not pass a default value to be used in case the property

 * <code>"prop"</code> is not defined, it has to check the result for

 * <code>null</code>:

 *

 * <pre>

 * Long tmp = java.security.AccessController.doPrivileged

 *     (new sun.security.action.GetLongAction("prop"));

 * long l;

 * if (tmp != null) {

 *     l = tmp.longValue();

 * }

 * </pre>

 *

 * <p>The following code retrieves the <code>Long</code> value of the system

 * property named <code>"prop"</code> as a privileged action, and also passes

 * a default value to be used in case the property <code>"prop"</code> is not

 * defined:

 *

 * <pre>

 * long l = java.security.AccessController.doPrivileged

 *      (new GetLongAction("prop")).longValue();

 * </pre>

 *

 * @author Roland Schemers

 * @see java.security.PrivilegedAction

 * @see java.security.AccessController

 * @since 1.2

 */

public class GetLongAction implements java.security.PrivilegedAction<Long> {

    private String theProp;

    private long defaultVal;

    private boolean defaultSet = false;

    /**

     * Constructor that takes the name of the system property whose

     * <code>Long</code> value needs to be determined.

     *

     * @param theProp the name of the system property.

     */

    public GetLongAction(String theProp) {

        this.theProp = theProp;

    }

    /**

     * Constructor that takes the name of the system property and the default

     * value of that property.

     *

     * @param theProp the name of the system property.

     * @param defaultVal the default value.

     */

    public GetLongAction(String theProp, long defaultVal) {

        this.theProp = theProp;

        this.defaultVal = defaultVal;

        this.defaultSet = true;

    }

    /**

     * Determines the <code>Long</code> value of the system property whose

     * name was specified in the constructor.

     *

     * <p>If there is no property of the specified name, or if the property

     * does not have the correct numeric format, then a <code>Long</code>

     * object representing the default value that was specified in the

     * constructor is returned, or <code>null</code> if no default value was

     * specified.

     *

     * @return the <code>Long</code> value of the property.

     */

    public Long run() {

        Long value = Long.getLong(theProp);

        if ((value == null) && defaultSet)

            return defaultVal;

        return value;

    }

}