Java example source code file (SunFileReader.java)

This example Java source code file (SunFileReader.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

audiofileformat, audiofilereader, audioinputstream, ioexception, net, network, sunfilereader, unsupportedaudiofileexception

The SunFileReader.java Java example source code

/*
 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.sun.media.sound;

import java.io.File;
import java.io.InputStream;
import java.io.IOException;
import java.io.DataInputStream;
import java.net.URL;

import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.UnsupportedAudioFileException;
import javax.sound.sampled.spi.AudioFileReader;



/**
 * Abstract File Reader class.
 *
 * @author Jan Borgersen
 */
abstract class SunFileReader extends AudioFileReader {

    // buffer size for temporary input streams
    protected static final int bisBufferSize = 4096;

    /**
     * Constructs a new SunFileReader object.
     */
    SunFileReader() {
    }


    // METHODS TO IMPLEMENT AudioFileReader

    /**
     * Obtains the audio file format of the input stream provided.  The stream must
     * point to valid audio file data.  In general, audio file providers may
     * need to read some data from the stream before determining whether they
     * support it.  These parsers must
     * be able to mark the stream, read enough data to determine whether they
     * support the stream, and, if not, reset the stream's read pointer to its original
     * position.  If the input stream does not support this, this method may fail
     * with an IOException.
     * @param stream the input stream from which file format information should be
     * extracted
     * @return an <code>AudioFileFormat object describing the audio file format
     * @throws UnsupportedAudioFileException if the stream does not point to valid audio
     * file data recognized by the system
     * @throws IOException if an I/O exception occurs
     * @see InputStream#markSupported
     * @see InputStream#mark
     */
    abstract public AudioFileFormat getAudioFileFormat(InputStream stream) throws UnsupportedAudioFileException, IOException;


    /**
     * Obtains the audio file format of the URL provided.  The URL must
     * point to valid audio file data.
     * @param url the URL from which file format information should be
     * extracted
     * @return an <code>AudioFileFormat object describing the audio file format
     * @throws UnsupportedAudioFileException if the URL does not point to valid audio
     * file data recognized by the system
     * @throws IOException if an I/O exception occurs
     */
    abstract public AudioFileFormat getAudioFileFormat(URL url) throws UnsupportedAudioFileException, IOException;


    /**
     * Obtains the audio file format of the File provided.  The File must
     * point to valid audio file data.
     * @param file the File from which file format information should be
     * extracted
     * @return an <code>AudioFileFormat object describing the audio file format
     * @throws UnsupportedAudioFileException if the File does not point to valid audio
     * file data recognized by the system
     * @throws IOException if an I/O exception occurs
     */
    abstract public AudioFileFormat getAudioFileFormat(File file) throws UnsupportedAudioFileException, IOException;


    /**
     * Obtains an audio stream from the input stream provided.  The stream must
     * point to valid audio file data.  In general, audio file providers may
     * need to read some data from the stream before determining whether they
     * support it.  These parsers must
     * be able to mark the stream, read enough data to determine whether they
     * support the stream, and, if not, reset the stream's read pointer to its original
     * position.  If the input stream does not support this, this method may fail
     * with an IOException.
     * @param stream the input stream from which the <code>AudioInputStream should be
     * constructed
     * @return an <code>AudioInputStream object based on the audio file data contained
     * in the input stream.
     * @throws UnsupportedAudioFileException if the stream does not point to valid audio
     * file data recognized by the system
     * @throws IOException if an I/O exception occurs
     * @see InputStream#markSupported
     * @see InputStream#mark
     */
    abstract public AudioInputStream getAudioInputStream(InputStream stream) throws UnsupportedAudioFileException, IOException;


    /**
     * Obtains an audio stream from the URL provided.  The URL must
     * point to valid audio file data.
     * @param url the URL for which the <code>AudioInputStream should be
     * constructed
     * @return an <code>AudioInputStream object based on the audio file data pointed
     * to by the URL
     * @throws UnsupportedAudioFileException if the URL does not point to valid audio
     * file data recognized by the system
     * @throws IOException if an I/O exception occurs
     */
    abstract public AudioInputStream getAudioInputStream(URL url) throws UnsupportedAudioFileException, IOException;


    /**
     * Obtains an audio stream from the File provided.  The File must
     * point to valid audio file data.
     * @param file the File for which the <code>AudioInputStream should be
     * constructed
     * @return an <code>AudioInputStream object based on the audio file data pointed
     * to by the File
     * @throws UnsupportedAudioFileException if the File does not point to valid audio
     * file data recognized by the system
     * @throws IOException if an I/O exception occurs
     */
    abstract public AudioInputStream getAudioInputStream(File file) throws UnsupportedAudioFileException, IOException;


    // HELPER METHODS



    /**
     * rllong
     * Protected helper method to read 64 bits and changing the order of
     * each bytes.
     * @param DataInputStream
     * @return 32 bits swapped value.
     * @exception IOException
     */
    final int rllong(DataInputStream dis) throws IOException {

        int b1, b2, b3, b4 ;
        int i = 0;

        i = dis.readInt();

        b1 = ( i & 0xFF ) << 24 ;
        b2 = ( i & 0xFF00 ) << 8;
        b3 = ( i & 0xFF0000 ) >> 8;
        b4 = ( i & 0xFF000000 ) >>> 24;

        i = ( b1 | b2 | b3 | b4 );

        return i;
    }

    /**
     * big2little
     * Protected helper method to swap the order of bytes in a 32 bit int
     * @param int
     * @return 32 bits swapped value
     */
    final int big2little(int i) {

        int b1, b2, b3, b4 ;

        b1 = ( i & 0xFF ) << 24 ;
        b2 = ( i & 0xFF00 ) << 8;
        b3 = ( i & 0xFF0000 ) >> 8;
        b4 = ( i & 0xFF000000 ) >>> 24;

        i = ( b1 | b2 | b3 | b4 );

        return i;
    }

    /**
     * rlshort
     * Protected helper method to read 16 bits value. Swap high with low byte.
     * @param DataInputStream
     * @return the swapped value.
     * @exception IOException
     */
    final short rlshort(DataInputStream dis)  throws IOException {

        short s=0;
        short high, low;

        s = dis.readShort();

        high = (short)(( s & 0xFF ) << 8) ;
        low = (short)(( s & 0xFF00 ) >>> 8);

        s = (short)( high | low );

        return s;
    }

    /**
     * big2little
     * Protected helper method to swap the order of bytes in a 16 bit short
     * @param int
     * @return 16 bits swapped value
     */
    final short big2littleShort(short i) {

        short high, low;

        high = (short)(( i & 0xFF ) << 8) ;
        low = (short)(( i & 0xFF00 ) >>> 8);

        i = (short)( high | low );

        return i;
    }

    /** Calculates the frame size for PCM frames.
     * Note that this method is appropriate for non-packed samples.
     * For instance, 12 bit, 2 channels will return 4 bytes, not 3.
     * @param sampleSizeInBits the size of a single sample in bits
     * @param channels the number of channels
     * @return the size of a PCM frame in bytes.
     */
    static final int calculatePCMFrameSize(int sampleSizeInBits, int channels) {
        return ((sampleSizeInBits + 7) / 8) * channels;
    }
}