| /* BasicPermission.java -- Implements a simple named permission. |
| Copyright (C) 1998, 1999 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., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| As a special exception, if you link this library with other files to |
| produce an executable, this library does not by itself cause the |
| resulting executable to be covered by the GNU General Public License. |
| This exception does not however invalidate any other reasons why the |
| executable file might be covered by the GNU General Public License. */ |
| |
| |
| package java.security; |
| |
| import java.io.Serializable; |
| import java.util.Hashtable; |
| import java.util.Enumeration; |
| |
| /** |
| * This class implements a simple model for named permissions without an |
| * associated action list. That is, either the named permission is granted |
| * or it is not. |
| * <p> |
| * It also supports trailing wildcards to allow the |
| * easy granting of permissions in a hierarchical fashion. (For example, |
| * the name "org.gnu.*" might grant all permissions under the "org.gnu" |
| * permissions hierarchy). The only valid wildcard character is a '*' |
| * which matches anything. It must be the rightmost element in the |
| * permission name and must follow a '.' or else the Permission name must |
| * consist of only a '*'. Any other occurrence of a '*' is not valid. |
| * <p> |
| * This class ignores the action list. Subclasses can choose to implement |
| * actions on top of this class if desired. |
| * |
| * @version 0.1 |
| * |
| * @author Aaron M. Renn (arenn@urbanophile.com) |
| */ |
| public abstract class BasicPermission extends Permission implements Serializable |
| { |
| |
| /*************************************************************************/ |
| |
| /* |
| * Constructors |
| */ |
| |
| /** |
| * This method initializes a new instance of <code>BasicPermission</code> |
| * with the specified name. If the name contains an illegal wildcard |
| * character, an exception is thrown. |
| * |
| * @param name The name of this permission. |
| * |
| * @exception IllegalArgumentException If the name contains an invalid wildcard character |
| * @exception NullPointerException If the name is null |
| */ |
| public |
| BasicPermission(String name) throws IllegalArgumentException, NullPointerException |
| { |
| super(name); |
| |
| if (name.indexOf("*") != -1) |
| { |
| if (!name.endsWith(".*") && !name.equals("*")) |
| throw new IllegalArgumentException("Bad wildcard: " + name); |
| |
| if (name.indexOf("*") != name.lastIndexOf("*")) |
| throw new IllegalArgumentException("Bad wildcard: " + name); |
| } |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * This method initializes a new instance of <code>BasicPermission</code> |
| * with the specified name. If the name contains an illegal wildcard |
| * character, an exception is thrown. The action list passed to this |
| * form of the constructor is ignored. |
| * |
| * @param name The name of this permission. |
| * @param actions The list of actions for this permission - ignored in this class. |
| * |
| * @exception IllegalArgumentException If the name contains an invalid wildcard character |
| * @exception NullPointerException If the name is null |
| */ |
| public |
| BasicPermission(String name, String actions) throws IllegalArgumentException, NullPointerException |
| { |
| // ignore actions |
| this(name); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * This method tests to see if the specified permission is implied by |
| * this permission. This will be true if the following conditions are met: |
| * <p> |
| * <ul> |
| * <li>The specified object is an instance of <code>BasicPermission</code>, |
| * or a subclass. |
| * <li>The name of the specified permission is identical to this permission's |
| * name or the name of the specified permission satisfies a wildcard match |
| * on this permission. |
| * </ul> |
| * |
| * @param perm The <code>Permission</code> object to test against. |
| * |
| * @return <code>true</code> if the specified permission is implied by this one or <code>false</code> otherwise. |
| */ |
| public boolean |
| implies(Permission perm) |
| { |
| if (!(perm instanceof BasicPermission)) |
| return false; |
| |
| String otherName = perm.getName(); |
| String name = getName(); |
| |
| if (name.equals(otherName)) |
| return true; |
| |
| int last = name.length() - 1; |
| if (name.charAt(last) == '*' |
| && otherName.startsWith(name.substring(0, last))) |
| return true; |
| |
| return false; |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * This method tests to see if this object is equal to the specified |
| * <code>Object</code>. This will be true if and only if the specified |
| * object meets the following conditions: |
| * <p> |
| * <ul> |
| * <li>It is an instance of <code>BasicPermission</code>, or a subclass. |
| * <li>It has the same name as this permission. |
| * </ul> |
| * |
| * @param obj The <code>Object</code> to test for equality against this object |
| * |
| * @return <code>true</code> if the specified <code>Object</code> is equal to this object or <code>false</code> otherwise. |
| */ |
| public boolean |
| equals(Object obj) |
| { |
| if (!(obj instanceof BasicPermission)) |
| return(false); |
| |
| if (!getName().equals(((BasicPermission)obj).getName())) |
| return(false); |
| |
| return(true); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * This method returns a hash code for this permission object. The hash |
| * code returned is the value returned by calling the <code>hashCode</code> |
| * method on the <code>String</code> that is the name of this permission. |
| * |
| * @return A hash value for this object |
| */ |
| public int |
| hashCode() |
| { |
| return(getName().hashCode()); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * This method returns a list of the actions associated with this |
| * permission. This method always returns the empty string ("") since |
| * this class ignores actions. |
| * |
| * @return The action list. |
| */ |
| public String |
| getActions() |
| { |
| return(""); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * This method returns an instance of <code>PermissionCollection</code> |
| * suitable for storing <code>BasicPermission</code> objects. This returns |
| * be a sub class of <code>PermissionCollection</code> |
| * that allows for an efficient and consistent implementation of |
| * the <code>implies</code> method. The collection doesn't handle subclasses |
| * of BasicPermission correctly; they must override this method. |
| * |
| * @return A new empty <code>PermissionCollection</code> object. |
| */ |
| public PermissionCollection |
| newPermissionCollection() |
| { |
| return new PermissionCollection() |
| { |
| Hashtable permissions = new Hashtable(); |
| boolean allAllowed = false; |
| |
| public void add(Permission permission) |
| { |
| if (isReadOnly()) |
| throw new IllegalStateException("readonly"); |
| |
| BasicPermission bp = (BasicPermission) permission; |
| String name = bp.getName(); |
| if (name.equals("*")) |
| allAllowed = true; |
| permissions.put(name, bp); |
| } |
| |
| public boolean implies(Permission permission) |
| { |
| if (!(permission instanceof BasicPermission)) |
| return false; |
| |
| if (allAllowed) |
| return true; |
| |
| BasicPermission toImply = (BasicPermission) permission; |
| String name = toImply.getName(); |
| if (name.equals("*")) |
| return false; |
| |
| int prefixLength = name.length(); |
| if (name.endsWith("*")) |
| prefixLength -= 2; |
| |
| while (true) { |
| if (permissions.get(name) != null) |
| return true; |
| |
| prefixLength = name.lastIndexOf('.', prefixLength); |
| if (prefixLength < 0) |
| return false; |
| name = name.substring(0, prefixLength + 1) + '*'; |
| } |
| } |
| |
| public Enumeration elements() |
| { |
| return permissions.elements(); |
| } |
| }; |
| } |
| } // class BasicPermission |