/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited

  *

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  *     http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package org.acegisecurity.context;

 import org.springframework.util.Assert;

 /**

  * A <code>ThreadLocal</code>-based implementation of {@link

  * org.acegisecurity.context.SecurityContextHolderStrategy}.

  *

  * @author Ben Alex

  * @version $Id: SecurityContextHolder.java 1324 2006-02-12 06:29:53Z benalex $

  *

  * @see java.lang.ThreadLocal

  * @see org.acegisecurity.context.HttpSessionContextIntegrationFilter

  */

 public class ThreadLocalSecurityContextHolderStrategy implements SecurityContextHolderStrategy {

     //~ Static fields/initializers =====================================================================================

     private static ThreadLocal contextHolder = new ThreadLocal();

     //~ Methods ========================================================================================================

     public void clearContext() {

         contextHolder.set(null);

     }

     public SecurityContext getContext() {

         if (contextHolder.get() == null) {

             contextHolder.set(new SecurityContextImpl());

         }

         return (SecurityContext) contextHolder.get();

     }

     public void setContext(SecurityContext context) {

         Assert.notNull(context, "Only non-null SecurityContext instances are permitted");

         contextHolder.set(context);

     }

 }