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diff --git a/libjava/classpath/java/security/AccessController.java b/libjava/classpath/java/security/AccessController.java
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+/* AccessController.java --- Access control context and permission checker
+   Copyright (C) 2001, 2004  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
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+package java.security;
+
+/**
+ * Access control context and permission checker.
+ * Can check permissions in the access control context of the current thread
+ * through the <code>checkPermission()</code> method.
+ * Manipulates the access control context for code that needs to be executed
+ * the protection domain of the calling class (by explicitly ignoring the
+ * context of the calling code) in the <code>doPrivileged()</code> methods.
+ * And provides a <code>getContext()</code> method which gives the access
+ * control context of the current thread that can be used for checking
+ * permissions at a later time and/or in another thread.
+ *
+ * @author Mark Wielaard (mark@klomp.org)
+ * @since 1.2
+ */
+public final class AccessController
+{
+  /**
+   * This class only has static methods so there is no public contructor.
+   */
+  private AccessController()
+  {
+  }
+
+  /**
+   * Checks wether the access control context of the current thread allows
+   * the given Permission. Throws an <code>AccessControlException</code>
+   * when the permission is not allowed in the current context. Otherwise
+   * returns silently without throwing an exception.
+   *
+   * @param perm the permission to be checked.
+   * @exception AccessControlException thrown if the current context does not
+   * allow the given permission.
+   */
+  public static void checkPermission(Permission perm)
+    throws AccessControlException
+  {
+    getContext().checkPermission(perm);
+  }
+
+  /**
+   * Calls the <code>run()</code> method of the given action with as
+   * (initial) access control context only the protection domain of the
+   * calling class. Calls to <code>checkPermission()</code> in the
+   * <code>run()</code> method ignore all earlier protection domains of
+   * classes in the call chain. Note that the protection domains of classes
+   * called by the code in the <code>run()</code> method are not ignored.
+   *
+   * @param action the <code>PrivilegedAction</code> whose <code>run()</code>
+   * should be be called.
+   * @return the result of the <code>action.run()</code> method.
+   */
+  public static Object doPrivileged(PrivilegedAction action)
+  {
+    VMAccessController.pushContext(null);
+    try
+      {
+        return action.run();
+      }
+    finally
+      {
+        VMAccessController.popContext();
+      }
+  }
+
+  /**
+   * Calls the <code>run()</code> method of the given action with as
+   * (initial) access control context the given context combined with the
+   * protection domain of the calling class. Calls to
+   * <code>checkPermission()</code> in the <code>run()</code> method ignore
+   * all earlier protection domains of classes in the call chain, but add
+   * checks for the protection domains given in the supplied context.
+   *
+   * @param action the <code>PrivilegedAction</code> whose <code>run()</code>
+   * should be be called.
+   * @param context the <code>AccessControlContext</code> whose protection
+   * domains should be added to the protection domain of the calling class.
+   * @return the result of the <code>action.run()</code> method.
+   */
+  public static Object doPrivileged(PrivilegedAction action,
+                                    AccessControlContext context)
+  {
+    VMAccessController.pushContext(context);
+    try
+      {
+        return action.run();
+      }
+    finally
+      {
+        VMAccessController.popContext();
+      }
+  }
+
+  /**
+   * Calls the <code>run()</code> method of the given action with as
+   * (initial) access control context only the protection domain of the
+   * calling class. Calls to <code>checkPermission()</code> in the
+   * <code>run()</code> method ignore all earlier protection domains of
+   * classes in the call chain. Note that the protection domains of classes
+   * called by the code in the <code>run()</code> method are not ignored.
+   * If the <code>run()</code> method throws an exception then this method
+   * will wrap that exception in an <code>PrivilegedActionException</code>.
+   *
+   * @param action the <code>PrivilegedExceptionAction</code> whose
+   * <code>run()</code> should be be called.
+   * @return the result of the <code>action.run()</code> method.
+   * @exception PrivilegedActionException wrapped around any exception that
+   * is thrown in the <code>run()</code> method.
+   */
+  public static Object doPrivileged(PrivilegedExceptionAction action)
+    throws PrivilegedActionException
+  {
+    VMAccessController.pushContext(null);
+    try
+      {
+        return action.run();
+      }
+    catch (Exception e)
+      {
+        throw new PrivilegedActionException(e);
+      }
+    finally
+      {
+        VMAccessController.popContext();
+      }
+  }
+
+  /**
+   * Calls the <code>run()</code> method of the given action with as
+   * (initial) access control context the given context combined with the
+   * protection domain of the calling class. Calls to
+   * <code>checkPermission()</code> in the <code>run()</code> method ignore
+   * all earlier protection domains of classes in the call chain, but add
+   * checks for the protection domains given in the supplied context.
+   * If the <code>run()</code> method throws an exception then this method
+   * will wrap that exception in an <code>PrivilegedActionException</code>.
+   *
+   * @param action the <code>PrivilegedExceptionAction</code> whose
+   * <code>run()</code> should be be called.
+   * @param context the <code>AccessControlContext</code> whose protection
+   * domains should be added to the protection domain of the calling class.
+   * @return the result of the <code>action.run()</code> method.
+   * @exception PrivilegedActionException wrapped around any exception that
+   * is thrown in the <code>run()</code> method.
+   */
+  public static Object doPrivileged(PrivilegedExceptionAction action,
+                                    AccessControlContext context)
+    throws PrivilegedActionException
+  {
+    VMAccessController.pushContext(context);
+    try
+      {
+        return action.run();
+      }
+    catch (Exception e)
+      {
+        throw new PrivilegedActionException(e);
+      }
+    finally
+      {
+        VMAccessController.popContext();
+      }
+  }
+
+  /**
+   * Returns the complete access control context of the current thread.
+   * The returned object encompasses all {@link ProtectionDomain} objects
+   * for all classes in the current call stack, or the set of protection
+   * domains until the last call to {@link
+   * #doPrivileged(java.security.PrivilegedAction)}.
+   *
+   * <p>Additionally, if a call was made to {@link
+   * #doPrivileged(java.security.PrivilegedAction,java.security.AccessControlContext)}
+   * that supplied an {@link AccessControlContext}, then that context
+   * will be intersected with the calculated one.
+   *
+   * @return The context.
+   */
+  public static AccessControlContext getContext()
+  {
+    return VMAccessController.getContext();
+  }
+}