001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.io.output;
018
019import java.io.Writer;
020
021/**
022 * Proxy stream that prevents the underlying writer from being closed.
023 * <p>
024 * This class is typically used in cases where a writer needs to be passed to a component that wants to explicitly close
025 * the writer even if other components would still use the writer for output.
026 * </p>
027 *
028 * @since 2.7
029 */
030public class CloseShieldWriter extends ProxyWriter {
031
032    /**
033     * Creates a proxy that shields the given writer from being closed.
034     *
035     * @param out underlying writer
036     */
037    public CloseShieldWriter(final Writer out) {
038        super(out);
039    }
040
041    /**
042     * Replaces the underlying writer with a {@link ClosedWriter} sentinel. The original writer will remain open, but
043     * this proxy will appear closed.
044     */
045    @Override
046    public void close() {
047        out = ClosedWriter.CLOSED_WRITER;
048    }
049
050}