/*

 * Copyright (c) 2015, 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.

 *

 * 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.

 */

import java.security.AccessController;

import java.security.Permission;

import java.security.Policy;

import java.security.PrivilegedAction;

import java.security.ProtectionDomain;

public class CustomPolicy extends Policy {

    // the ProtectionDomain of CustomPolicy

    private final ProtectionDomain policyPd;

    public CustomPolicy() {

        policyPd = AccessController.doPrivileged(

            (PrivilegedAction<ProtectionDomain>)

                () -> this.getClass().getProtectionDomain());

    }

    @Override

    public boolean implies(ProtectionDomain pd, Permission perm) {

        System.out.println("CustomPolicy.implies");

        // If the protection domain is the same as CustomPolicy, then

        // we return true. This is to prevent recursive permission checks

        // that lead to StackOverflow errors when the policy implementation

        // performs a sensitive operation that triggers a permission check,

        // for example, as below.

        if (pd == policyPd) {

            return true;

        }

        // Do something that triggers a permission check to make sure that

        // we don't cause a StackOverflow error.

        String home = AccessController.doPrivileged(

            (PrivilegedAction<String>) () -> System.getProperty("user.home"));

        return true;

    }

}