javax.sound.sampled
Class AudioInputStream

java.lang.Object   
  java.io.InputStream   
      javax.sound.sampled.AudioInputStream

All Implemented Interfaces:

Closeable

public class AudioInputStream
extends InputStream   

An audio input stream is an input stream with a specified audio format and length. The length is expressed in sample frames, not bytes. Several methods are provided for reading a certain number of bytes from the stream, or an unspecified number of bytes. The audio input stream keeps track of the last byte that was read. You can skip over an arbitrary number of bytes to get to a later position for reading. An audio input stream may support marks. When you set a mark, the current position is remembered so that you can return to it later.

The AudioSystem class includes many methods that manipulate AudioInputStream objects. For example, the methods let you:

• obtain an audio input stream from an external audio file, stream, or URL
• write an external file from an audio input stream
• convert an audio input stream to a different audio format

Since:

1.3

See Also:

AudioSystem , Clip.open(AudioInputStream)

Field Summary

protected AudioFormat	format The format of the audio data contained in the stream.
protected long	frameLength This stream's length, in sample frames.
protected long	framePos The current position in this stream, in sample frames (zero-based).
protected int	frameSize The size of each frame, in bytes.

Constructor Summary

AudioInputStream (InputStream stream, AudioFormat format, long length)
Constructs an audio input stream that has the requested format and length in sample frames, using audio data from the specified input stream.

AudioInputStream (TargetDataLine line)
Constructs an audio input stream that reads its data from the target data line indicated.

Method Summary

int	available () Returns the maximum number of bytes that can be read (or skipped over) from this audio input stream without blocking.
void	close () Closes this audio input stream and releases any system resources associated with the stream.
AudioFormat	getFormat () Obtains the audio format of the sound data in this audio input stream.
long	getFrameLength () Obtains the length of the stream, expressed in sample frames rather than bytes.
void	mark (int readlimit) Marks the current position in this audio input stream.
boolean	markSupported () Tests whether this audio input stream supports the mark and reset methods.
int	read () Reads the next byte of data from the audio input stream.
int	read (byte[] b) Reads some number of bytes from the audio input stream and stores them into the buffer array b.
int	read (byte[] b, int off, int len) Reads up to a specified maximum number of bytes of data from the audio stream, putting them into the given byte array.
void	reset () Repositions this audio input stream to the position it had at the time its mark method was last invoked.
long	skip (long n) Skips over and discards a specified number of bytes from this audio input stream.

Methods inherited from class java.lang.Object

clone , equals , finalize , getClass , hashCode , notify , notifyAll , toString , wait , wait , wait

Field Detail

format

protected AudioFormat    format

The format of the audio data contained in the stream.

frameLength

protected long frameLength

This stream's length, in sample frames.

frameSize

protected int frameSize

The size of each frame, in bytes.

framePos

protected long framePos

The current position in this stream, in sample frames (zero-based).

Constructor Detail

AudioInputStream

public AudioInputStream(InputStream    stream,
                        AudioFormat    format,
                        long length)

Constructs an audio input stream that has the requested format and length in sample frames, using audio data from the specified input stream.

Parameters:

stream - the stream on which this AudioInputStream object is based

format - the format of this stream's audio data

length - the length in sample frames of the data in this stream

AudioInputStream

public AudioInputStream(TargetDataLine    line)

Constructs an audio input stream that reads its data from the target data line indicated. The format of the stream is the same as that of the target data line, and the length is AudioSystem#NOT_SPECIFIED.

Parameters:

line - the target data line from which this stream obtains its data.

See Also:

AudioSystem.NOT_SPECIFIED

Method Detail

getFormat

public AudioFormat    getFormat()

Obtains the audio format of the sound data in this audio input stream.

Returns:

an audio format object describing this stream's format

getFrameLength

public long getFrameLength()

Obtains the length of the stream, expressed in sample frames rather than bytes.

Returns:

the length in sample frames

read

public int read()
         throws IOException   

Reads the next byte of data from the audio input stream. The audio input stream's frame size must be one byte, or an IOException will be thrown.

Specified by:

read in class InputStream

Returns:

the next byte of data, or -1 if the end of the stream is reached

Throws:

IOException - if an input or output error occurs

See Also:

read(byte[], int, int) , read(byte[]) ,

read

public int read(byte[] b)
         throws IOException   

Reads some number of bytes from the audio input stream and stores them into the buffer array b. The number of bytes actually read is returned as an integer. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

This method will always read an integral number of frames. If the length of the array is not an integral number of frames, a maximum of b.length - (b.length % frameSize) bytes will be read.

Overrides:

read in class InputStream

Parameters:

b - the buffer into which the data is read

Returns:

the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached

Throws:

IOException - if an input or output error occurs

See Also:

read(byte[], int, int) , read() , available()

read

public int read(byte[] b,
                int off,
                int len)
         throws IOException   

Reads up to a specified maximum number of bytes of data from the audio stream, putting them into the given byte array.

This method will always read an integral number of frames. If len does not specify an integral number of frames, a maximum of len - (len % frameSize) bytes will be read.

Overrides:

read in class InputStream

Parameters:

b - the buffer into which the data is read

off - the offset, from the beginning of array b, at which the data will be written

len - the maximum number of bytes to read

Returns:

the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached

Throws:

IOException - if an input or output error occurs

See Also:

read(byte[]) , read() , skip(long) , available()

skip

public long skip(long n)
          throws IOException   

Skips over and discards a specified number of bytes from this audio input stream.

Overrides:

skip in class InputStream

Parameters:

n - the requested number of bytes to be skipped

Returns:

the actual number of bytes skipped

Throws:

IOException - if an input or output error occurs

See Also:

read() , available()

available

public int available()
              throws IOException   

Returns the maximum number of bytes that can be read (or skipped over) from this audio input stream without blocking. This limit applies only to the next invocation of a read or skip method for this audio input stream; the limit can vary each time these methods are invoked. Depending on the underlying stream,an IOException may be thrown if this stream is closed.

Overrides:

available in class InputStream

Returns:

the number of bytes that can be read from this audio input stream without blocking

Throws:

IOException - if an input or output error occurs

See Also:

read(byte[], int, int) , read(byte[]) , read() , skip(long)

close

public void close()
           throws IOException   

Closes this audio input stream and releases any system resources associated with the stream.

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

Throws:

IOException - if an input or output error occurs

mark

public void mark(int readlimit)

Marks the current position in this audio input stream.

Overrides:

mark in class InputStream

Parameters:

readlimit - the maximum number of bytes that can be read before the mark position becomes invalid.

See Also:

reset() , markSupported()

reset

public void reset()
           throws IOException   

Repositions this audio input stream to the position it had at the time its mark method was last invoked.

Overrides:

reset in class InputStream

Throws:

IOException - if an input or output error occurs.

See Also:

mark(int) , markSupported()

markSupported

public boolean markSupported()

Tests whether this audio input stream supports the mark and reset methods.

Overrides:

markSupported in class InputStream

Returns:

true if this stream supports the mark and reset methods; false otherwise

See Also:

mark(int) , reset()