com.sun.media.imageio.stream

Class FileChannelImageInputStream

public class FileChannelImageInputStream extends ImageInputStreamImpl

A class which implements ImageInputStream using a FileChannel as the eventual data source. The channel contents are assumed to be stable during the lifetime of the object.

Memory mapping and new I/O view Buffers are used to read the data. Only methods which provide significant performance improvement with respect to the superclass implementation are overridden. Overridden methods are not commented individually unless some noteworthy aspect of the implementation must be described.

The methods of this class are not synchronized.

See Also: javax.imageio.stream.ImageInputStream java.nio java.nio.channels.FileChannel

Constructor Summary
	FileChannelImageInputStream(FileChannel channel) Constructs a `FileChannelImageInputStream` from a `FileChannel`.

Method Summary
void	close() Invokes the superclass method and sets the internal reference to the source `FileChannel` to `null`.
long	length() Returns the number of bytes currently in the `FileChannel`.
int	read()
int	read(byte[] b, int off, int len)
void	readFully(char[] c, int off, int len)
void	readFully(short[] s, int off, int len)
void	readFully(int[] i, int off, int len)
void	readFully(long[] l, int off, int len)
void	readFully(float[] f, int off, int len)
void	readFully(double[] d, int off, int len)
void	seek(long pos) Invokes the superclass method and sets the position within the memory mapped buffer.
void	setByteOrder(ByteOrder networkByteOrder)

Constructor Detail

FileChannelImageInputStream

public FileChannelImageInputStream(FileChannel channel)

Constructs a FileChannelImageInputStream from a FileChannel. The initial position of the stream stream is taken to be the position of the FileChannel parameter when this constructor is invoked. The stream and flushed positions are therefore both initialized to channel.position().

Parameters: channel the source FileChannel.

Throws: IllegalArgumentException if channel is null or is not open. IOException if a method invoked on channel throws an IOException.

Method Detail

close

public void close()

Invokes the superclass method and sets the internal reference to the source FileChannel to null. The source FileChannel is not closed.

Throws: IOException if an error occurs.

length

public long length()

Returns the number of bytes currently in the FileChannel. If an IOException is encountered when querying the channel's size, -1L will be returned.

Returns: The number of bytes in the channel -1L to indicate unknown length.