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 *      https://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 */
017
018package org.apache.commons.io;
019
020import java.io.IOException;
021
022/**
023 * A IOException associated with a source index.
024 *
025 * @since 2.7
026 */
027public class IOIndexedException extends IOException {
028
029    private static final long serialVersionUID = 1L;
030
031    /**
032     * Converts input to a suitable String for exception message.
033     *
034     * @param index An index into a source collection.
035     * @param cause A cause.
036     * @return A message.
037     */
038    protected static String toMessage(final int index, final Throwable cause) {
039        // Letting index be any int
040        final String unspecified = "Null";
041        final String name = cause == null ? unspecified : cause.getClass().getSimpleName();
042        final String msg = cause == null ? unspecified : cause.getMessage();
043        return String.format("%s #%,d: %s", name, index, msg);
044    }
045
046    /**
047     * Index.
048     */
049    private final int index;
050
051    /**
052     * Constructs a new exception.
053     *
054     * @param index index of this exception.
055     * @param cause cause exceptions.
056     */
057    public IOIndexedException(final int index, final Throwable cause) {
058        super(toMessage(index, cause), cause);
059        this.index = index;
060    }
061
062    /**
063     * The index of this exception.
064     *
065     * @return index of this exception.
066     */
067    public int getIndex() {
068        return index;
069    }
070
071}