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.util;
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   /**
027    * Constructor.
028    *
029    * @param out The wrapped output stream.
030    * @param characterEncoding The character encoding of the output stream.
031    * @param autoFlush Automatically flush after every println.
032    * @throws IOException
033    */
034   public FinishablePrintWriter(OutputStream out, String characterEncoding, boolean autoFlush) throws IOException {
035      super(new OutputStreamWriter(out, characterEncoding), autoFlush);
036      f = (out instanceof Finishable ? (Finishable)out : null);
037   }
038
039   /**
040    * Calls {@link Finishable#finish()} on the underlying output stream.
041    *
042    * <p>
043    * A no-op if the underlying output stream does not implement the {@link Finishable} interface.
044    */
045   @Override /* Finishable */
046   public void finish() throws IOException {
047      if (f != null)
048         f.finish();
049   }
050}