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.rest;
014
015import java.io.*;
016
017import org.apache.juneau.encoders.*;
018
019/**
020 * A wrapped {@link PrintWriter} with an added <code>finish()</code> method.
021 */
022public class FinishablePrintWriter extends PrintWriter implements Finishable {
023
024   final Finishable f;
025
026   FinishablePrintWriter(OutputStream out, String characterEncoding) throws IOException {
027      super(new OutputStreamWriter(out, characterEncoding));
028      f = (out instanceof Finishable ? (Finishable)out : null);
029   }
030
031
032   /**
033    * Calls {@link Finishable#finish()} on the underlying output stream.
034    * 
035    * <p>
036    * A no-op if the underlying output stream does not implement the {@link Finishable} interface.
037    */
038   @Override /* Finishable */
039   public void finish() throws IOException {
040      if (f != null)
041         f.finish();
042   }
043}