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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You 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.

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package com.sun.org.apache.xml.internal.utils;

/**

 * This class pools string buffers, since they are reused so often.

 * String buffers are good candidates for pooling, because of

 * their supporting character arrays.

 * @xsl.usage internal

 */

public class StringBufferPool

{

  /** The global pool of string buffers.   */

  private static ObjectPool m_stringBufPool =

    new ObjectPool(com.sun.org.apache.xml.internal.utils.FastStringBuffer.class);

  /**

   * Get the first free instance of a string buffer, or create one

   * if there are no free instances.

   *

   * @return A string buffer ready for use.

   */

  public synchronized static FastStringBuffer get()

  {

    return (FastStringBuffer) m_stringBufPool.getInstance();

  }

  /**

   * Return a string buffer back to the pool.

   *

   * @param sb Must be a non-null reference to a string buffer.

   */

  public synchronized static void free(FastStringBuffer sb)

  {

    // Since this isn't synchronized, setLength must be

    // done before the instance is freed.

    // Fix attributed to Peter Speck <speck@ruc.dk>.

    sb.setLength(0);

    m_stringBufPool.freeInstance(sb);

  }

}