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 */ 17 package org.apache.commons.io.output; 18 19 import java.io.IOException; 20 import 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 */ 33 public 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 */ write(int b)46 public void write(int b) throws IOException { 47 throw new IOException("write(" + b + ") failed: stream is closed"); 48 } 49 50 } 51