Merge JDK 1.4 java.security changes from classpath.

* java/security/AccessControlException.java: Merge from Classpath.
       * java/security/AccessController.java: Likewise.
       * java/security/AllPermission.java: Likewise.
       * java/security/BasicPermission.java: Likewise.
       * java/security/Certificate.java: Likewise.
       * java/security/CodeSource.java: Likewise.
       * java/security/DigestException.java: Likewise.
       * java/security/DigestOutputStream.java: Likewise.
       * java/security/DomainCombiner.java: Likewise.
       * java/security/GeneralSecurityException.java: Likewise.
       * java/security/Guard.java: Likewise.
       * java/security/GuardedObject.java: Likewise.
       * java/security/InvalidAlgorithmParameterException.java: Likewise.
       * java/security/InvalidKeyException.java: Likewise.
       * java/security/InvalidParameterException.java: Likewise.
       * java/security/Key.java: Likewise.
       * java/security/KeyException.java: Likewise.
       * java/security/KeyManagementException.java: Likewise.
       * java/security/KeyStoreException.java: Likewise.
       * java/security/MessageDigest.java: Likewise.
       * java/security/NoSuchAlgorithmException.java: Likewise.
       * java/security/NoSuchProviderException.java: Likewise.
       * java/security/Permission.java: Likewise.
       * java/security/PermissionCollection.java: Likewise.
       * java/security/Permissions.java: Likewise.
       * java/security/Policy.java: Likewise.
       * java/security/Principal.java: Likewise.
       * java/security/PrivateKey.java: Likewise.
       * java/security/PrivilegedAction.java: Likewise.
       * java/security/PrivilegedActionException.java: Likewise.
       * java/security/PrivilegedExceptionAction.java: Likewise.
       * java/security/ProtectionDomain.java: Likewise.
       * java/security/ProviderException.java: Likewise.
       * java/security/PublicKey.java: Likewise.
       * java/security/SecureClassLoader.java: Likewise.
       * java/security/SecurityPermission.java: Likewise.
       * java/security/SignatureException.java: Likewise.
       * java/security/UnrecoverableKeyException.java: Likewise.
       * java/security/UnresolvedPermission.java: Likewise.
       * java/security/acl/AclNotFoundException.java: Likewise.
       * java/security/acl/LastOwnerException.java: Likewise.
       * java/security/acl/NotOwnerException.java: Likewise.
       * java/security/cert/CRLException.java: Likewise.
       * java/security/cert/CertificateEncodingException.java: Likewise.
       * java/security/cert/CertificateException.java: Likewise.
       * java/security/cert/CertificateExpiredException.java: Likewise.
       * java/security/cert/CertificateFactory.java: Likewise.
       * java/security/cert/CertificateNotYetValidException.java: Likewise.
       * java/security/cert/CertificateParsingException.java: Likewise.
       * java/security/spec/InvalidKeySpecException.java: Likewise.
       * java/security/spec/InvalidParameterSpecException.java: Likewise.

       * java/security/cert/CertPath.java: New file.
       * java/security/cert/CertPathBuilderException.java: New file.
       * java/security/cert/CertPathValidatorException.java: New file.
       * java/security/cert/CertStoreException.java: New file.

       * Makefile.am: Add new CertPath classes.
       * Makefile.in: Rebuilt.

       * gnu/java/util/EmptyEnumeration: New file from classpath.

From-SVN: r53837

libjava/java/security/GuardedObject.java

@@ -1,5 +1,5 @@
 /* GuardedObject.java -- An object protected by a Guard
-   Copyright (C) 1998 Free Software Foundation, Inc.
+   Copyright (C) 1998, 2002 Free Software Foundation, Inc.
 
 This file is part of GNU Classpath.
 
@@ -38,38 +38,50 @@ exception statement from your version. */
 package java.security;
 
 import java.io.Serializable;
+import java.io.IOException;
+import java.io.ObjectOutputStream;
 
 /**
  * This class is an object that is guarded by a <code>Guard</code> object.
- * The object that is being guarded is retrieved by a call to the only 
+ * The object that is being guarded is retrieved by a call to the only
  * method in this class - <code>getObject</code>.  That method returns the
- * guarded <code>Object</code> after first checking with the 
+ * guarded <code>Object</code> after first checking with the
  * <code>Guard</code>.  If the <code>Guard</code> disallows access, an
  * exception will be thrown.
  *
- * @version 0.0
- *
- * @author Aaron M. Renn (arenn@urbanophile.com)
+ * @author Aaron M. Renn <arenn@urbanophile.com>
+ * @since 1.1
+ * @status updated to 1.4
  */
 public class GuardedObject implements Serializable
 {
   /**
-   * This is the Guard that is protecting the object.
+   * Compatible with JDK 1.1+.
    */
-  private Guard guard;
+  private static final long serialVersionUID = -5240450096227834308L;
+
+  /**
+   * This is the Guard that is protecting the object.
+   *
+   * @serial the guard
+   */
+  private final Guard guard;
 
   /**
    * This is the object that is being guarded.
+   *
+   * @serial the protected object
    */
-  private Object object;
+  private final Object object;
 
   /**
    * This method initializes a new instance of <code>GuardedObject</code>
    * that protects the specified <code>Object</code> using the specified
-   * <code>Guard</code>
+   * <code>Guard</code>. A null guard means there are no restrictions on
+   * accessing the object.
    *
-   * @param object The <code>Object</code> to guard
-   * @param guard The <code>Guard</code> that is protecting the object.
+   * @param object the <code>Object</code> to guard
+   * @param guard the <code>Guard</code> that is protecting the object
    */
   public GuardedObject(Object object, Guard guard)
   {
@@ -78,18 +90,31 @@ public class GuardedObject implements Serializable
   }
 
   /**
-   * This method first call the <code>checkGuard</code> method on the 
-   * <code>Guard</code> object protecting the guarded object.  If the 
+   * This method first call the <code>checkGuard</code> method on the
+   * <code>Guard</code> object protecting the guarded object.  If the
    * <code>Guard</code> disallows access, an exception is thrown, otherwise
    * the <code>Object</code> is returned.
    *
    * @return The object being guarded
-   *
-   * @exception SecurityException If the <code>Guard</code> disallows access to the object.
+   * @throws SecurityException if access is denied
    */
-  public Object getObject() throws SecurityException
+  public Object getObject()
   {
-    guard.checkGuard(object);
-    return (object);
+    if (guard != null)
+      guard.checkGuard(object);
+    return object;
   }
-}
+
+  /**
+   * Ensures that serialization is legal, by checking the guard.
+   *
+   * @param s the stream to write to
+   * @throws IOException if the underlying stream fails
+   */
+  private void writeObject(ObjectOutputStream s) throws IOException
+  {
+    if (guard != null)
+      guard.checkGuard(object);
+    s.defaultWriteObject();
+  }
+} // class GuardedObject