Java tutorial
/* * Copyright (c) 1998, 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. 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.security; import java.security.*; import java.util.Enumeration; import java.util.Hashtable; import java.util.StringTokenizer; import sun.security.util.SecurityConstants; /** * The AllPermission is a permission that implies all other permissions. * <p> * <b>Note:</b> Granting AllPermission should be done with extreme care, * as it implies all other permissions. Thus, it grants code the ability * to run with security * disabled. Extreme caution should be taken before granting such * a permission to code. This permission should be used only during testing, * or in extremely rare cases where an application or applet is * completely trusted and adding the necessary permissions to the policy * is prohibitively cumbersome. * * @see java.security.Permission * @see java.security.AccessController * @see java.security.Permissions * @see java.security.PermissionCollection * @see java.lang.SecurityManager * * * @author Roland Schemers * @since 1.2 * * @serial exclude */ public final class AllPermission extends Permission { private static final long serialVersionUID = -2916474571451318075L; /** * Creates a new AllPermission object. */ public AllPermission() { super("<all permissions>"); } /** * Creates a new AllPermission object. This * constructor exists for use by the {@code Policy} object * to instantiate new Permission objects. * * @param name ignored * @param actions ignored. */ public AllPermission(String name, String actions) { this(); } /** * Checks if the specified permission is "implied" by * this object. This method always returns true. * * @param p the permission to check against. * * @return return */ public boolean implies(Permission p) { return true; } /** * Checks two AllPermission objects for equality. Two AllPermission * objects are always equal. * * @param obj the object we are testing for equality with this object. * @return true if {@code obj} is an AllPermission, false otherwise. */ public boolean equals(Object obj) { return (obj instanceof AllPermission); } /** * Returns the hash code value for this object. * * @return a hash code value for this object. */ public int hashCode() { return 1; } /** * Returns the canonical string representation of the actions. * * @return the actions. */ public String getActions() { return "<all actions>"; } /** * Returns a new PermissionCollection object for storing AllPermission * objects. * * @return a new PermissionCollection object suitable for * storing AllPermissions. */ public PermissionCollection newPermissionCollection() { return new AllPermissionCollection(); } } /** * A AllPermissionCollection stores a collection * of AllPermission permissions. AllPermission objects * must be stored in a manner that allows them to be inserted in any * order, but enable the implies function to evaluate the implies * method in an efficient (and consistent) manner. * * @see java.security.Permission * @see java.security.Permissions * * * @author Roland Schemers * * @serial include */ final class AllPermissionCollection extends PermissionCollection implements java.io.Serializable { // use serialVersionUID from JDK 1.2.2 for interoperability private static final long serialVersionUID = -4023755556366636806L; private boolean all_allowed; // true if any all permissions have been added /** * Create an empty AllPermissions object. * */ public AllPermissionCollection() { all_allowed = false; } /** * Adds a permission to the AllPermissions. The key for the hash is * permission.path. * * @param permission the Permission object to add. * * @exception IllegalArgumentException - if the permission is not a * AllPermission * * @exception SecurityException - if this AllPermissionCollection object * has been marked readonly */ public void add(Permission permission) { if (!(permission instanceof AllPermission)) throw new IllegalArgumentException("invalid permission: " + permission); if (isReadOnly()) throw new SecurityException("attempt to add a Permission to a readonly PermissionCollection"); all_allowed = true; // No sync; staleness OK } /** * Check and see if this set of permissions implies the permissions * expressed in "permission". * * @param permission the Permission object to compare * * @return always returns true. */ public boolean implies(Permission permission) { return all_allowed; // No sync; staleness OK } /** * Returns an enumeration of all the AllPermission objects in the * container. * * @return an enumeration of all the AllPermission objects. */ public Enumeration<Permission> elements() { return new Enumeration<>() { private boolean hasMore = all_allowed; public boolean hasMoreElements() { return hasMore; } public Permission nextElement() { hasMore = false; return SecurityConstants.ALL_PERMISSION; } }; } }