001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.wicket.markup.html.internal; 018 019import org.apache.wicket.markup.MarkupStream; 020import org.apache.wicket.request.Response; 021import org.apache.wicket.request.cycle.RequestCycle; 022import org.apache.wicket.response.StringResponse; 023 024/** 025 * Utility class that buffers output and maintains markup stream index 026 * 027 * @author igor.vaynberg 028 */ 029public abstract class ResponseBufferZone 030{ 031 private final RequestCycle cycle; 032 private final MarkupStream stream; 033 034 public ResponseBufferZone(RequestCycle cycle, MarkupStream stream) 035 { 036 this.cycle = cycle; 037 this.stream = stream; 038 } 039 040 public CharSequence execute() 041 { 042 final int originalStreamPos = stream.getCurrentIndex(); 043 044 final Response original = cycle.getResponse(); 045 046 final StringResponse buffer = new StringResponse(); 047 cycle.setResponse(buffer); 048 try 049 { 050 executeInsideBufferedZone(); 051 return buffer.getBuffer(); 052 } 053 finally 054 { 055 cycle.setResponse(original); 056 stream.setCurrentIndex(originalStreamPos); 057 } 058 } 059 060 protected abstract void executeInsideBufferedZone(); 061}