/*

 * Copyright (c) 2007, 2011, 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.nio.file;

import java.security.BasicPermission;

/**

 * The {@code Permission} class for link creation operations.

 *

 * <p> The following table provides a summary description of what the permission

 * allows, and discusses the risks of granting code the permission.

 *

 * <table border=1 cellpadding=5

 *        summary="Table shows permission target name, what the permission allows, and associated risks">

 * <tr>

 * <th>Permission Target Name</th>

 * <th>What the Permission Allows</th>

 * <th>Risks of Allowing this Permission</th>

 * </tr>

 * <tr>

 *   <td>hard</td>

 *   <td> Ability to add an existing file to a directory. This is sometimes

 *   known as creating a link, or hard link. </td>

 *   <td> Extreme care should be taken when granting this permission. It allows

 *   linking to any file or directory in the file system thus allowing the

 *   attacker access to all files. </td>

 * </tr>

 * <tr>

 *   <td>symbolic</td>

 *   <td> Ability to create symbolic links. </td>

 *   <td> Extreme care should be taken when granting this permission. It allows

 *   linking to any file or directory in the file system thus allowing the

 *   attacker to access to all files. </td>

 * </tr>

 * </table>

 *

 * @since 1.7

 *

 * @see Files#createLink

 * @see Files#createSymbolicLink

 */

public final class LinkPermission extends BasicPermission {

    static final long serialVersionUID = -1441492453772213220L;

    private void checkName(String name) {

        if (!name.equals("hard") && !name.equals("symbolic")) {

            throw new IllegalArgumentException("name: " + name);

        }

    }

    /**

     * Constructs a {@code LinkPermission} with the specified name.

     *

     * @param   name

     *          the name of the permission. It must be "hard" or "symbolic".

     *

     * @throws  IllegalArgumentException

     *          if name is empty or invalid

     */

    public LinkPermission(String name) {

        super(name);

        checkName(name);

    }

    /**

     * Constructs a {@code LinkPermission} with the specified name.

     *

     * @param   name

     *          the name of the permission; must be "hard" or "symbolic".

     * @param   actions

     *          the actions for the permission; must be the empty string or

     *          {@code null}

     *

     * @throws  IllegalArgumentException

     *          if name is empty or invalid, or actions is a non-empty string

     */

    public LinkPermission(String name, String actions) {

        super(name);

        checkName(name);

        if (actions != null && actions.length() > 0) {

            throw new IllegalArgumentException("actions: " + actions);

        }

    }

}