| /** |
| * Copyright (C) 2006 Google Inc. |
| * |
| * 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 com.google.inject.servlet; |
| |
| import com.google.inject.OutOfScopeException; |
| import java.io.IOException; |
| import javax.servlet.Filter; |
| import javax.servlet.FilterChain; |
| import javax.servlet.FilterConfig; |
| import javax.servlet.ServletException; |
| import javax.servlet.ServletRequest; |
| import javax.servlet.ServletResponse; |
| import javax.servlet.http.HttpServletRequest; |
| import javax.servlet.http.HttpServletResponse; |
| |
| /** |
| * Apply this filter to all requests where you plan to use servlet scopes. |
| * |
| * @author crazybob@google.com (Bob Lee) |
| */ |
| public class GuiceFilter implements Filter { |
| |
| static final ThreadLocal<Context> localContext = new ThreadLocal<Context>(); |
| |
| public void doFilter(ServletRequest servletRequest, |
| ServletResponse servletResponse, FilterChain filterChain) |
| throws IOException, ServletException { |
| Context previous = localContext.get(); |
| try { |
| localContext.set(new Context((HttpServletRequest) servletRequest, |
| (HttpServletResponse) servletResponse)); |
| filterChain.doFilter(servletRequest, servletResponse); |
| } finally { |
| localContext.set(previous); |
| } |
| } |
| |
| static HttpServletRequest getRequest() { |
| return getContext().getRequest(); |
| } |
| |
| static HttpServletResponse getResponse() { |
| return getContext().getResponse(); |
| } |
| |
| static Context getContext() { |
| Context context = localContext.get(); |
| if (context == null) { |
| throw new OutOfScopeException("Cannot access scoped object. Either we" |
| + " are not currently inside an HTTP Servlet request, or you may" |
| + " have forgotten to apply " + GuiceFilter.class.getName() |
| + " as a servlet filter for this request."); |
| } |
| return context; |
| } |
| |
| static class Context { |
| |
| final HttpServletRequest request; |
| final HttpServletResponse response; |
| |
| Context(HttpServletRequest request, HttpServletResponse response) { |
| this.request = request; |
| this.response = response; |
| } |
| |
| HttpServletRequest getRequest() { |
| return request; |
| } |
| |
| HttpServletResponse getResponse() { |
| return response; |
| } |
| } |
| |
| public void init(FilterConfig filterConfig) throws ServletException {} |
| |
| public void destroy() {} |
| } |