https://openjdk.java.net/ 
/*
 * 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.DataInputStream;
import java.io.EOFException;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;

import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.UnsupportedAudioFileException;




WAVE file reader.

Author:Kara Kytle, Jan Borgersen, Florian Bomers
/**
 * WAVE file reader.
 *
 * @author Kara Kytle
 * @author Jan Borgersen
 * @author Florian Bomers
 */
public final class WaveFileReader extends SunFileReader {

    private static final int MAX_READ_LENGTH = 12;

    
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.

Params:
  • stream – the input stream from which file format information should be
extracted
Throws:
See Also:
Returns:an AudioFileFormat object describing the audio file format
/**
     * 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</code> 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
     */
    public AudioFileFormat getAudioFileFormat(InputStream stream) throws UnsupportedAudioFileException, IOException {
        // fix for 4489272: AudioSystem.getAudioFileFormat() fails for InputStream, but works for URL
        AudioFileFormat aff = getFMT(stream, true);
        // the following is not strictly necessary - but was implemented like that in 1.3.0 - 1.4.1
        // so I leave it as it was. May remove this for 1.5.0
        stream.reset();
        return aff;
    }


    
Obtains the audio file format of the URL provided.  The URL must
point to valid audio file data.

Params:
  • url – the URL from which file format information should be
extracted
Throws:
Returns:an AudioFileFormat object describing the audio file format
/**
     * 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</code> 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
     */
    public AudioFileFormat getAudioFileFormat(URL url) throws UnsupportedAudioFileException, IOException {
        InputStream urlStream = url.openStream(); // throws IOException
        AudioFileFormat fileFormat = null;
        try {
            fileFormat = getFMT(urlStream, false);
        } finally {
            urlStream.close();
        }
        return fileFormat;
    }


    
Obtains the audio file format of the File provided.  The File must
point to valid audio file data.

Params:
  • file – the File from which file format information should be
extracted
Throws:
Returns:an AudioFileFormat object describing the audio file format
/**
     * 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</code> 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
     */
    public AudioFileFormat getAudioFileFormat(File file) throws UnsupportedAudioFileException, IOException {
        AudioFileFormat fileFormat = null;
        FileInputStream fis = new FileInputStream(file);       // throws IOException
        // part of fix for 4325421
        try {
            fileFormat = getFMT(fis, false);
        } finally {
            fis.close();
        }

        return fileFormat;
    }


    
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.

Params:
  • stream – the input stream from which the AudioInputStream should be
constructed
Throws:
See Also:
Returns:an AudioInputStream object based on the audio file data contained
in the input stream.
/**
     * 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</code> should be
     * constructed
     * @return an <code>AudioInputStream</code> 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
     */
    public AudioInputStream getAudioInputStream(InputStream stream) throws UnsupportedAudioFileException, IOException {
        // getFMT leaves the input stream at the beginning of the audio data
        AudioFileFormat fileFormat = getFMT(stream, true); // throws UnsupportedAudioFileException, IOException

        // we've got everything, and the stream is at the
        // beginning of the audio data, so return an AudioInputStream.
        return new AudioInputStream(stream, fileFormat.getFormat(), fileFormat.getFrameLength());
    }


    
Obtains an audio stream from the URL provided.  The URL must
point to valid audio file data.

Params:
  • url – the URL for which the AudioInputStream should be
constructed
Throws:
Returns:an AudioInputStream object based on the audio file data pointed
to by the URL
/**
     * 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</code> should be
     * constructed
     * @return an <code>AudioInputStream</code> 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
     */
    public AudioInputStream getAudioInputStream(URL url) throws UnsupportedAudioFileException, IOException {
        InputStream urlStream = url.openStream();  // throws IOException
        AudioFileFormat fileFormat = null;
        try {
            fileFormat = getFMT(urlStream, false);
        } finally {
            if (fileFormat == null) {
                urlStream.close();
            }
        }
        return new AudioInputStream(urlStream, fileFormat.getFormat(), fileFormat.getFrameLength());
    }


    
Obtains an audio stream from the File provided.  The File must
point to valid audio file data.

Params:
  • file – the File for which the AudioInputStream should be
constructed
Throws:
Returns:an AudioInputStream object based on the audio file data pointed
to by the File
/**
     * 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</code> should be
     * constructed
     * @return an <code>AudioInputStream</code> 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
     */
    public AudioInputStream getAudioInputStream(File file) throws UnsupportedAudioFileException, IOException {
        FileInputStream fis = new FileInputStream(file); // throws IOException
        AudioFileFormat fileFormat = null;
        // part of fix for 4325421
        try {
            fileFormat = getFMT(fis, false);
        } finally {
            if (fileFormat == null) {
                fis.close();
            }
        }
        return new AudioInputStream(fis, fileFormat.getFormat(), fileFormat.getFrameLength());
    }


    //--------------------------------------------------------------------


    private AudioFileFormat getFMT(InputStream stream, boolean doReset) throws UnsupportedAudioFileException, IOException {

        // assumes sream is rewound

        int bytesRead;
        int nread = 0;
        int fmt;
        int length = 0;
        int wav_type = 0;
        short channels;
        long sampleRate;
        long avgBytesPerSec;
        short blockAlign;
        int sampleSizeInBits;
        AudioFormat.Encoding encoding = null;

        DataInputStream dis = new DataInputStream( stream );

        if (doReset) {
            dis.mark(MAX_READ_LENGTH);
        }

        int magic = dis.readInt();
        int fileLength = rllong(dis);
        int waveMagic = dis.readInt();
        int totallength;
        if (fileLength <= 0) {
            fileLength = AudioSystem.NOT_SPECIFIED;
            totallength = AudioSystem.NOT_SPECIFIED;
        } else {
            totallength = fileLength + 8;
        }

        if ((magic != WaveFileFormat.RIFF_MAGIC) || (waveMagic != WaveFileFormat.WAVE_MAGIC)) {
            // not WAVE, throw UnsupportedAudioFileException
            if (doReset) {
                dis.reset();
            }
            throw new UnsupportedAudioFileException("not a WAVE file");
        }

        // find and read the "fmt" chunk
        // we break out of this loop either by hitting EOF or finding "fmt "
        while(true) {

            try {
                fmt = dis.readInt();
                nread += 4;
                if( fmt==WaveFileFormat.FMT_MAGIC ) {
                    // we've found the 'fmt' chunk
                    break;
                } else {
                    // else not 'fmt', skip this chunk
                    length = rllong(dis);
                    nread += 4;
                    if (length % 2 > 0) length++;
                    nread += dis.skipBytes(length);
                }
            } catch (EOFException eof) {
                                // we've reached the end of the file without finding the 'fmt' chunk
                throw new UnsupportedAudioFileException("Not a valid WAV file");
            }
        }

        // Read the format chunk size.
        length = rllong(dis);
        nread += 4;

        // This is the nread position at the end of the format chunk
        int endLength = nread + length;

        // Read the wave format data out of the format chunk.

        // encoding.
        wav_type = rlshort(dis); nread += 2;

        if (wav_type == WaveFileFormat.WAVE_FORMAT_PCM)
            encoding = AudioFormat.Encoding.PCM_SIGNED;  // if 8-bit, we need PCM_UNSIGNED, below...
        else if ( wav_type == WaveFileFormat.WAVE_FORMAT_ALAW )
            encoding = AudioFormat.Encoding.ALAW;
        else if ( wav_type == WaveFileFormat.WAVE_FORMAT_MULAW )
            encoding = AudioFormat.Encoding.ULAW;
        else {
            // we don't support any other WAVE formats....
            throw new UnsupportedAudioFileException("Not a supported WAV file");
        }
        // channels
        channels = rlshort(dis); nread += 2;
        if (channels <= 0) {
            throw new UnsupportedAudioFileException("Invalid number of channels");
        }

        // sample rate.
        sampleRate = rllong(dis); nread += 4;

        // this is the avgBytesPerSec
        avgBytesPerSec = rllong(dis); nread += 4;

        // this is blockAlign value
        blockAlign = rlshort(dis); nread += 2;

        // this is the PCM-specific value bitsPerSample
        sampleSizeInBits = (int)rlshort(dis); nread += 2;
        if (sampleSizeInBits <= 0) {
            throw new UnsupportedAudioFileException("Invalid bitsPerSample");
        }

        // if sampleSizeInBits==8, we need to use PCM_UNSIGNED
        if ((sampleSizeInBits==8) && encoding.equals(AudioFormat.Encoding.PCM_SIGNED))
            encoding = AudioFormat.Encoding.PCM_UNSIGNED;

        // skip any difference between the length of the format chunk
        // and what we read

        // if the length of the chunk is odd, there's an extra pad byte
        // at the end.  i've never seen this in the fmt chunk, but we
        // should check to make sure.

        if (length % 2 != 0) length += 1;

        // $$jb: 07.28.99: endLength>nread, not length>nread.
        //       This fixes #4257986
        if (endLength > nread)
            nread += dis.skipBytes(endLength - nread);

        // we have a format now, so find the "data" chunk
        // we break out of this loop either by hitting EOF or finding "data"
        // $$kk: if "data" chunk precedes "fmt" chunk we are hosed -- can this legally happen?
        nread = 0;
        while(true) {
            try{
                int datahdr = dis.readInt();
                nread+=4;
                if (datahdr == WaveFileFormat.DATA_MAGIC) {
                    // we've found the 'data' chunk
                    break;
                } else {
                    // else not 'data', skip this chunk
                    int thisLength = rllong(dis); nread += 4;
                    if (thisLength % 2 > 0) thisLength++;
                    nread += dis.skipBytes(thisLength);
                }
            } catch (EOFException eof) {
                // we've reached the end of the file without finding the 'data' chunk
                throw new UnsupportedAudioFileException("Not a valid WAV file");
            }
        }
        // this is the length of the data chunk
        int dataLength = rllong(dis); nread += 4;

        // now build the new AudioFileFormat and return

        AudioFormat format = new AudioFormat(encoding,
                                             (float)sampleRate,
                                             sampleSizeInBits, channels,
                                             calculatePCMFrameSize(sampleSizeInBits, channels),
                                             (float)sampleRate, false);

        return new WaveFileFormat(AudioFileFormat.Type.WAVE,
                                  totallength,
                                  format,
                                  dataLength / format.getFrameSize());
    }
}