    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.IOException;
    020import java.io.OutputStream;
    021
    022/**
    023 * Never writes data. Calls never go beyond this class.
    024 * <p>
    025 * This output stream has no destination (file/socket etc.) and all bytes written to it are ignored and lost.
    026 * </p>
    027 */
    028public class NullOutputStream extends OutputStream {
    029
    030    /**
    031     * The singleton instance.
    032     *
    033     * @since 2.12.0
    034     */
    035    public static final NullOutputStream INSTANCE = new NullOutputStream();
    036
    037    /**
    038     * The singleton instance.
    039     *
    040     * @deprecated Use {@link #INSTANCE}.
    041     */
    042    @Deprecated
    043    public static final NullOutputStream NULL_OUTPUT_STREAM = INSTANCE;
    044
    045    /**
    046     * Deprecated in favor of {@link #INSTANCE}.
    047     *
    048     * TODO: Will be private in 3.0.
    049     *
    050     * @deprecated Use {@link #INSTANCE}.
    051     */
    052    @Deprecated
    053    public NullOutputStream() {
    054    }
    055
    056    /**
    057     * Does nothing - output to {@code /dev/null}.
    058     *
    059     * @param b The bytes to write
    060     * @throws IOException never
    061     */
    062    @Override
    063    public void write(final byte[] b) throws IOException {
    064        // To /dev/null
    065    }
    066
    067    /**
    068     * Does nothing - output to {@code /dev/null}.
    069     *
    070     * @param b The bytes to write
    071     * @param off The start offset
    072     * @param len The number of bytes to write
    073     */
    074    @Override
    075    public void write(final byte[] b, final int off, final int len) {
    076        // To /dev/null
    077    }
    078
    079    /**
    080     * Does nothing - output to {@code /dev/null}.
    081     *
    082     * @param b The byte to write
    083     */
    084    @Override
    085    public void write(final int b) {
    086        // To /dev/null
    087    }
    088
    089}