    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}