1/*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements.  See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License.  You may obtain a copy of the License at
8 *
9 *      http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17package org.apache.commons.io.output;
18
19import java.io.IOException;
20import java.io.OutputStream;
21
22/**
23 * Closed output stream. This stream throws an exception on all attempts to
24 * write something to the stream.
25 * <p>
26 * Typically uses of this class include testing for corner cases in methods
27 * that accept an output stream and acting as a sentinel value instead of
28 * a <code>null</code> output stream.
29 *
30 * @version $Id: ClosedOutputStream.java 601751 2007-12-06 14:55:45Z niallp $
31 * @since Commons IO 1.4
32 */
33public class ClosedOutputStream extends OutputStream {
34
35    /**
36     * A singleton.
37     */
38    public static final ClosedOutputStream CLOSED_OUTPUT_STREAM = new ClosedOutputStream();
39
40    /**
41     * Throws an {@link IOException} to indicate that the stream is closed.
42     *
43     * @param b ignored
44     * @throws IOException always thrown
45     */
46    public void write(int b) throws IOException {
47        throw new IOException("write(" + b + ") failed: stream is closed");
48    }
49
50}
51