| /* |
| Copyright (C) 2005 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package javax.sound.sampled; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| |
| /** |
| * This is an InputStream which is specialized for reading audio files. |
| * In particular it only allows operations to act on a multiple of |
| * the audio stream's frame size. |
| * @since 1.3 |
| */ |
| public class AudioInputStream extends InputStream |
| { |
| /** The format of the audio stream. */ |
| protected AudioFormat format; |
| |
| /** The length of the audio stream in frames. */ |
| protected long frameLength; |
| |
| /** The current frame position, starting from frame zero. */ |
| protected long framePos; |
| |
| /** The size of a frame in bytes. */ |
| protected int frameSize; |
| |
| // I wonder why this class doesn't inherit from FilterInputStream. |
| private InputStream input; |
| |
| // The saved frame position, used for mark/reset. |
| private long markedFramePos; |
| |
| /** |
| * Create a new AudioInputStream given an underlying InputStream, |
| * the audio format, and the length of the data in frames. The |
| * frame size is taken from the format. |
| * @param is the underlying input stream |
| * @param fmt the format of the data |
| * @param length the length of the data in frames |
| */ |
| public AudioInputStream(InputStream is, AudioFormat fmt, long length) |
| { |
| this.format = fmt; |
| this.frameLength = length; |
| this.framePos = 0; |
| this.frameSize = fmt.getFrameSize(); |
| this.input = is; |
| } |
| |
| /** |
| * Create a new AudioInputStream given a TargetDataLine. The audio |
| * format and the frame size are taken from the line. |
| * @param line the TargetDataLine |
| */ |
| public AudioInputStream(TargetDataLine line) |
| { |
| this(new TargetInputStream(line), line.getFormat(), |
| AudioSystem.NOT_SPECIFIED); |
| } |
| |
| /** |
| * Return the number of bytes available to be read from the |
| * underlying stream. This wrapper method ensures that the result |
| * is always a multiple of the frame size. |
| */ |
| public int available() throws IOException |
| { |
| int result = input.available(); |
| // Ensure result is a multiple of the frame size. |
| if (frameSize != AudioSystem.NOT_SPECIFIED) |
| result -= result % frameSize; |
| return result; |
| } |
| |
| /** |
| * Close the stream. |
| */ |
| public void close() throws IOException |
| { |
| input.close(); |
| } |
| |
| /** |
| * Get the format associated with this stream. |
| * @return the AudioFormat |
| */ |
| public AudioFormat getFormat() |
| { |
| return format; |
| } |
| |
| /** |
| * Get the length of this stream in frames. Note that this |
| * may be AudioSystem#NOT_SPECIFIED. |
| * @return the length of the stream in frames |
| */ |
| public long getFrameLength() |
| { |
| return frameLength; |
| } |
| |
| public void mark(int limit) |
| { |
| input.mark(limit); |
| markedFramePos = framePos; |
| } |
| |
| /** |
| * Return true if the underlying stream supports mark and reset, |
| * false otherwise. |
| */ |
| public boolean markSupported() |
| { |
| return input.markSupported(); |
| } |
| |
| /** |
| * Read a single byte from the underlying stream. If the frame |
| * size is set, and is not one byte, an IOException will be thrown. |
| */ |
| public int read() throws IOException |
| { |
| if (frameSize != 1) |
| throw new IOException("frame size must be 1 for read()"); |
| int result; |
| if (framePos == frameLength) |
| result = -1; |
| else |
| result = input.read(); |
| if (result != -1) |
| ++framePos; |
| return result; |
| } |
| |
| public int read(byte[] buf) throws IOException |
| { |
| return read(buf, 0, buf.length); |
| } |
| |
| public int read(byte[] buf, int offset, int length) throws IOException |
| { |
| int result; |
| if (framePos == frameLength) |
| result = -1; |
| else |
| { |
| int myFrameSize = (frameSize == AudioSystem.NOT_SPECIFIED |
| ? 1 : frameSize); |
| // Ensure length is a multiple of frame size. |
| length -= length % myFrameSize; |
| |
| result = 0; |
| while (result == 0 || result % myFrameSize != 0) |
| { |
| int val = input.read(buf, offset, length); |
| if (val < 0) |
| { |
| // This is a weird situation as we might have read a |
| // frame already. It isn't clear at all what to do if |
| // we only found a partial frame. For now we just |
| // return whatever we did find. |
| if (result == 0) |
| return -1; |
| result -= result % myFrameSize; |
| break; |
| } |
| result += val; |
| } |
| // assert result % myFrameSize == 0; |
| framePos += result / myFrameSize; |
| } |
| return result; |
| } |
| |
| public void reset() throws IOException |
| { |
| input.reset(); |
| framePos = markedFramePos; |
| } |
| |
| public long skip(long n) throws IOException |
| { |
| if (frameSize != AudioSystem.NOT_SPECIFIED) |
| n -= n % frameSize; |
| long actual = input.skip(n); |
| if (frameSize != AudioSystem.NOT_SPECIFIED) |
| framePos += actual / frameSize; |
| return actual; |
| } |
| |
| private static class TargetInputStream extends InputStream |
| { |
| private TargetDataLine line; |
| private byte[] buf; |
| |
| /** |
| * Create a new TargetInputStream. |
| * @param line the line to wrap |
| */ |
| public TargetInputStream(TargetDataLine line) |
| { |
| this.line = line; |
| // FIXME: do we have to call line.open()? |
| } |
| |
| public synchronized int read() throws IOException |
| { |
| if (buf == null) |
| buf = new byte[1]; |
| int count = read(buf, 0, 1); |
| if (count < 0) |
| return -1; |
| return buf[0]; |
| } |
| |
| public int read(byte[] buf, int offset, int length) throws IOException |
| { |
| return line.read(buf, offset, length); |
| } |
| } |
| } |