001// Licensed under the Apache License, Version 2.0 (the "License"); 002// you may not use this file except in compliance with the License. 003// You may obtain a copy of the License at 004// 005// http://www.apache.org/licenses/LICENSE-2.0 006// 007// Unless required by applicable law or agreed to in writing, software 008// distributed under the License is distributed on an "AS IS" BASIS, 009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 010// See the License for the specific language governing permissions and 011// limitations under the License. 012 013package org.apache.tapestry5.internal.services; 014 015import org.apache.tapestry5.internal.InternalConstants; 016import org.apache.tapestry5.internal.structure.Page; 017import org.apache.tapestry5.ioc.util.UnknownValueException; 018import org.apache.tapestry5.services.*; 019 020import java.io.IOException; 021 022/** 023 * A filter, used only in production mode, that does a "pre-flight check" that the indicated component 024 * actually exists. If it does not, then the handling of the component event is aborted and other 025 * hooks will ensure that request ultimately becomes a 404. 026 * 027 * @since 5.4 028 */ 029public class ProductionModeUnknownComponentFilter implements ComponentRequestFilter 030{ 031 private final Request request; 032 033 private final RequestPageCache cache; 034 035 public ProductionModeUnknownComponentFilter(Request request, RequestPageCache cache) 036 { 037 this.request = request; 038 this.cache = cache; 039 } 040 041 @Override 042 public void handleComponentEvent(ComponentEventRequestParameters parameters, ComponentRequestHandler handler) throws IOException 043 { 044 Page containerPage = cache.get(parameters.getContainingPageName()); 045 046 try 047 { 048 containerPage.getComponentElementByNestedId(parameters.getNestedComponentId()); 049 050 handler.handleComponentEvent(parameters); 051 052 } catch (UnknownValueException ex) 053 { 054 request.setAttribute(InternalConstants.REFERENCED_COMPONENT_NOT_FOUND, true); 055 } 056 } 057 058 @Override 059 public void handlePageRender(PageRenderRequestParameters parameters, ComponentRequestHandler handler) throws IOException 060 { 061 // Pass these through to the default handler. 062 handler.handlePageRender(parameters); 063 } 064}