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.imaging.common.bytesource;
018
019import java.io.BufferedInputStream;
020import java.io.ByteArrayOutputStream;
021import java.io.File;
022import java.io.FileInputStream;
023import java.io.IOException;
024import java.io.InputStream;
025import java.io.RandomAccessFile;
026
027import org.apache.commons.imaging.common.BinaryFunctions;
028
029public class ByteSourceFile extends ByteSource {
030    private final File file;
031
032    public ByteSourceFile(final File file) {
033        super(file.getName());
034        this.file = file;
035    }
036
037    @Override
038    public InputStream getInputStream() throws IOException {
039        return new BufferedInputStream(new FileInputStream(file));
040    }
041
042    @Override
043    public byte[] getBlock(final long start, final int length) throws IOException {
044        try (RandomAccessFile raf = new RandomAccessFile(file, "r")) {
045            // We include a separate check for int overflow.
046            if ((start < 0) || (length < 0) || (start + length < 0)
047                    || (start + length > raf.length())) {
048                throw new IOException("Could not read block (block start: "
049                        + start + ", block length: " + length
050                        + ", data length: " + raf.length() + ").");
051            }
052
053            return BinaryFunctions.getRAFBytes(raf, start, length,
054                    "Could not read value from file");
055        }
056    }
057
058    @Override
059    public long getLength() {
060        return file.length();
061    }
062
063    @Override
064    public byte[] getAll() throws IOException {
065        final ByteArrayOutputStream baos = new ByteArrayOutputStream();
066
067        try (InputStream is = getInputStream()) {
068            final byte[] buffer = new byte[1024];
069            int read;
070            while ((read = is.read(buffer)) > 0) {
071                baos.write(buffer, 0, read);
072            }
073            return baos.toByteArray();
074        }
075    }
076
077    @Override
078    public String getDescription() {
079        return "File: '" + file.getAbsolutePath() + "'";
080    }
081
082}