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.input;
018
019import java.io.InputStream;
020
021/**
022 *
023 * An {@link InputStream} that infinitely repeats provided bytes.
024 * <p>
025 * Closing a <tt>InfiniteCircularInputStream</tt> has no effect. The methods in
026 * this class can be called after the stream has been closed without generating
027 * an <tt>IOException</tt>.
028 *
029 */
030public class InfiniteCircularInputStream extends InputStream {
031
032    final private byte[] repeatedContent;
033    private int position = -1;
034
035    /**
036     * Creates a InfiniteCircularStream from the specified array of chars.
037     *
038     * @param repeatedContent
039     *            Input buffer to be repeated (not copied)
040     */
041    public InfiniteCircularInputStream(final byte[] repeatedContent) {
042        this.repeatedContent = repeatedContent;
043    }
044
045    @Override
046    public int read() {
047        position = (position + 1) % repeatedContent.length;
048        return repeatedContent[position] & 0xff; // copied from
049                                                 // java.io.ByteArrayInputStream.read()
050    }
051
052}