001// ***************************************************************************************************************************
002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file *
003// * distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file        *
004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance            *
005// * with the License.  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 distributed under the License is distributed on an  *
010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the        *
011// * specific language governing permissions and limitations under the License.                                              *
012// ***************************************************************************************************************************
013package org.apache.juneau.internal;
014
015import java.io.*;
016
017/**
018 * Similar to {@link StringWriter}, but uses a {@link StringBuilder} instead to avoid synchronization overhead.
019 *
020 * <h5 class='section'>Notes:</h5><ul>
021 *    <li class='warn'>This class is not thread safe.
022 * </ul>
023 *
024 * <h5 class='section'>See Also:</h5><ul>
025
026 * </ul>
027 */
028public final class StringBuilderWriter extends Writer {
029
030   private StringBuilder sb;
031
032   /**
033    * Create a new string writer using the default initial string-builder size.
034    */
035   public StringBuilderWriter() {
036      sb = new StringBuilder();
037      lock = null;
038   }
039
040   /**
041    * Create a new string writer around an existing string builder.
042    *
043    * @param sb The string builder being wrapped.
044    */
045   public StringBuilderWriter(StringBuilder sb) {
046      this.sb = sb;
047      lock = null;
048   }
049
050   /**
051    * Create a new string writer using the specified initial string-builder size.
052    *
053    * @param initialSize
054    *    The number of <tt>char</tt> values that will fit into this buffer before it is automatically expanded.
055    * @throws IllegalArgumentException If <tt>initialSize</tt> is negative.
056    */
057   public StringBuilderWriter(int initialSize) {
058      sb = new StringBuilder(initialSize);
059      lock = null;
060   }
061
062   @Override /* Writer */
063   public void write(int c) {
064      sb.append((char) c);
065   }
066
067   @Override /* Writer */
068   public void write(char cbuf[], int start, int length) {
069      sb.append(cbuf, start, length);
070   }
071
072   @Override /* Writer */
073   public void write(String str) {
074      sb.append(str);
075   }
076
077   @Override /* Writer */
078   public void write(String str, int off, int len) {
079      sb.append(str.substring(off, off + len));
080   }
081
082   @Override /* Writer */
083   public StringBuilderWriter append(CharSequence csq) {
084      if (csq == null)
085         write("null");
086      else
087         write(csq.toString());
088      return this;
089   }
090
091   @Override /* Writer */
092   public StringBuilderWriter append(CharSequence csq, int start, int end) {
093      CharSequence cs = (csq == null ? "null" : csq);
094      write(cs.subSequence(start, end).toString());
095      return this;
096   }
097
098   @Override /* Writer */
099   public StringBuilderWriter append(char c) {
100      write(c);
101      return this;
102   }
103
104   @Override /* Object */
105   public String toString() {
106      return sb.toString();
107   }
108
109   @Override /* Writer */
110   public void flush() {}
111
112   @Override /* Writer */
113   public void close() throws IOException {}
114}