| /* PermissionCollection.java -- A collection of permission objects |
| Copyright (C) 1998, 2001, 2002, 2005 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
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| exception statement from your version. */ |
| |
| package java.security; |
| |
| import java.io.Serializable; |
| import java.util.Enumeration; |
| |
| /** |
| * This class models a group of Java permissions. It has convenient |
| * methods for determining whether or not a given permission is implied |
| * by any of the permissions in this collection. |
| * |
| * <p>Some care must be taken in storing permissions. First, a collection of |
| * the appropriate type must be created. This is done by calling the |
| * <code>newPermissionCollection</code> method on an object of the |
| * permission class you wish to add to the collection. If this method |
| * returns <code>null</code>, any type of <code>PermissionCollection</code> |
| * can be used to store permissions of that type. However, if a |
| * <code>PermissionCollection</code> collection object is returned, that |
| * type must be used. |
| * |
| * <p>A <code>PermissionCollection</code> returned by the |
| * <code>newPermissionCollection</code> method in a subclass of |
| * <code>Permission</code> is a homogeneous collection. It only will |
| * hold permissions of one specified type - instances of the class that |
| * created it. Not all <code>PermissionCollection</code> subclasses |
| * have to hold permissions of only one type however. For example, |
| * the <code>Permissions</code> class holds permissions of many types. |
| * |
| * <p>Since the <code>newPermissionCollection</code> in <code>Permission</code> |
| * itself returns <code>null</code>, by default a permission can be stored |
| * in any type of collection unless it overrides that method to create its |
| * own collection type. |
| * |
| * @author Aaron M. Renn (arenn@urbanophile.com) |
| * @author Eric Blake (ebb9@email.byu.edu) |
| * @see Permission |
| * @see Permissions |
| * @since 1.1 |
| * @status updated to 1.4 |
| */ |
| public abstract class PermissionCollection implements Serializable |
| { |
| /** |
| * Compatible with JDK 1.1+. |
| */ |
| private static final long serialVersionUID = -6727011328946861783L; |
| |
| /** |
| * Indicates whether or not this collection is read only. |
| * |
| * @serial if the collection is read-only |
| */ |
| private boolean readOnly; |
| |
| /** |
| * Create a new collection. |
| */ |
| public PermissionCollection() |
| { |
| } |
| |
| /** |
| * This method adds a new <code>Permission</code> object to the collection. |
| * |
| * @param perm the <code>Permission</code> to add |
| * |
| * @throws SecurityException if the collection is marked read only |
| * @throws IllegalArgumentException if perm is of the wrong type |
| */ |
| public abstract void add(Permission perm); |
| |
| /** |
| * This method tests whether the specified <code>Permission</code> object is |
| * implied by this collection of <code>Permission</code> objects. |
| * |
| * @param perm the <code>Permission</code> object to test |
| * @return true if the collection implies perm |
| */ |
| public abstract boolean implies(Permission perm); |
| |
| /** |
| * This method returns an <code>Enumeration</code> of all the objects in |
| * this collection. |
| * |
| * @return an <code>Enumeration</code> of this collection's objects |
| */ |
| public abstract Enumeration elements(); |
| |
| /** |
| * This method sets this <code>PermissionCollection</code> object to be |
| * read only. No further permissions can be added to it after calling this |
| * method. |
| */ |
| public void setReadOnly() |
| { |
| readOnly = true; |
| } |
| |
| /** |
| * This method tests whether or not this <code>PermissionCollection</code> |
| * object is read only. |
| * |
| * @return true if this collection is read only |
| */ |
| public boolean isReadOnly() |
| { |
| return readOnly; |
| } |
| |
| /** |
| * This method returns a <code>String</code> representation of this |
| * collection. It is formed by: |
| * <pre> |
| * super.toString()" (\n" |
| * // enumerate all permissions, one per line |
| * ")\n" |
| * </pre> |
| * |
| * @return a <code>String</code> representing this object |
| */ |
| public String toString() |
| { |
| StringBuffer sb = new StringBuffer(super.toString()); |
| |
| sb.append(" (\n"); |
| Enumeration e = elements(); |
| while (e.hasMoreElements()) |
| sb.append(' ').append(e.nextElement()).append('\n'); |
| return sb.append(")\n").toString(); |
| } |
| } // class PermissionCollection |