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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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.
*
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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</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
*/
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</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
*/
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</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
*/
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</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
*/
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</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
*/
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</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
*/
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;
}
}