    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.IOException;
    020import java.io.Reader;
    021
    022/**
    023 * Broken reader. This reader always throws an {@link IOException} from
    024 * all the {@link Reader} methods where the exception is declared.
    025 * <p>
    026 * This class is mostly useful for testing error handling in code that uses a
    027 * reader.
    028 * </p>
    029 *
    030 * @since 2.7
    031 */
    032public class BrokenReader extends Reader {
    033
    034    /**
    035     * The exception that is thrown by all methods of this class.
    036     */
    037    private final IOException exception;
    038
    039    /**
    040     * Creates a new reader that always throws the given exception.
    041     *
    042     * @param exception the exception to be thrown
    043     */
    044    public BrokenReader(final IOException exception) {
    045        this.exception = exception;
    046    }
    047
    048    /**
    049     * Creates a new reader that always throws an {@link IOException}
    050     */
    051    public BrokenReader() {
    052        this(new IOException("Broken reader"));
    053    }
    054
    055    /**
    056     * Throws the configured exception.
    057     *
    058     * @param cbuf ignored
    059     * @param off ignored
    060     * @param len ignored
    061     * @return nothing
    062     * @throws IOException always thrown
    063     */
    064    @Override
    065    public int read(final char[] cbuf, final int off, final int len) throws IOException {
    066        throw exception;
    067    }
    068
    069    /**
    070     * Throws the configured exception.
    071     *
    072     * @param n ignored
    073     * @return nothing
    074     * @throws IOException always thrown
    075     */
    076    @Override
    077    public long skip(final long n) throws IOException {
    078        throw exception;
    079    }
    080
    081    /**
    082     * Throws the configured exception.
    083     *
    084     * @return nothing
    085     * @throws IOException always thrown
    086     */
    087    @Override
    088    public boolean ready() throws IOException {
    089        throw exception;
    090    }
    091
    092    /**
    093     * Throws the configured exception.
    094     *
    095     * @param readAheadLimit ignored
    096     * @throws IOException always thrown
    097     */
    098    @Override
    099    public void mark(final int readAheadLimit) throws IOException {
    100        throw exception;
    101    }
    102
    103    /**
    104     * Throws the configured exception.
    105     *
    106     * @throws IOException always thrown
    107     */
    108    @Override
    109    public synchronized void reset() throws IOException {
    110        throw exception;
    111    }
    112
    113    /**
    114     * Throws the configured exception.
    115     *
    116     * @throws IOException always thrown
    117     */
    118    @Override
    119    public void close() throws IOException {
    120        throw exception;
    121    }
    122
    123}