001// Copyright 2005 The Apache Software Foundation 002// 003// Licensed under the Apache License, Version 2.0 (the "License"); 004// you may not use this file except in compliance with the License. 005// You may obtain a copy of the License at 006// 007// http://www.apache.org/licenses/LICENSE-2.0 008// 009// Unless required by applicable law or agreed to in writing, software 010// distributed under the License is distributed on an "AS IS" BASIS, 011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012// See the License for the specific language governing permissions and 013// limitations under the License. 014 015package org.apache.tapestry.markup; 016 017import java.io.CharArrayWriter; 018import java.io.PrintWriter; 019 020import org.apache.tapestry.IMarkupWriter; 021import org.apache.tapestry.NestedMarkupWriter; 022 023/** 024 * Nested implementation of {@link org.apache.tapestry.IMarkupWriter}. Accumulates content in a 025 * {@link java.io.CharArrayWriter}, and prints the buffered content (raw) on {@link #close()}. 026 * 027 * @author Howard M. Lewis Ship 028 * @since 4.0 029 * @see org.apache.tapestry.IMarkupWriter#getNestedWriter() 030 */ 031public class NestedMarkupWriterImpl extends MarkupWriterImpl implements NestedMarkupWriter 032{ 033 private final IMarkupWriter _parent; 034 035 private final CharArrayWriter _charArrayWriter; 036 037 private boolean _closed; 038 039 public String getBuffer() 040 { 041 if (_closed) 042 throw new IllegalStateException(MarkupMessages.closeOnce()); 043 044 _closed = true; 045 046 super.close(); 047 048 return _charArrayWriter.toString(); 049 } 050 051 public NestedMarkupWriterImpl(IMarkupWriter parent, MarkupFilter filter) 052 { 053 // Need to do this awkward double constructor because we want 054 // to create an object and pass it to the parent constructor. 055 // Java language rules get in the way here. 056 057 this(parent, new CharArrayWriter(), filter); 058 } 059 060 private NestedMarkupWriterImpl(IMarkupWriter parent, CharArrayWriter writer, MarkupFilter filter) 061 { 062 super(parent.getContentType(), new PrintWriter(writer), filter); 063 064 _parent = parent; 065 _charArrayWriter = writer; 066 } 067 068 /** 069 * Closes the internal {@link CharArrayWriter}, then captures its content and invokes 070 * {@link org.apache.tapestry.IMarkupWriter#printRaw(String)} on the parent markup writer 071 * (the writer that created this writer). 072 */ 073 074 public void close() 075 { 076 String content = getBuffer(); 077 078 _parent.printRaw(content); 079 } 080}