Package org.apache.xmlgraphics.image.codec.util

Class ForwardSeekableStream

java.lang.Object

java.io.InputStream

org.apache.xmlgraphics.image.codec.util.SeekableStream

org.apache.xmlgraphics.image.codec.util.ForwardSeekableStream

All Implemented Interfaces:

Closeable, DataInput, AutoCloseable

public class ForwardSeekableStream
extends SeekableStream

A subclass of SeekableStream that may be used to wrap a regular InputStream efficiently. Seeking backwards is not supported.

Field Summary

Fields inherited from class org.apache.xmlgraphics.image.codec.util.SeekableStream

markPos

Constructor Summary

Constructors

Constructor	Description
ForwardSeekableStream(InputStream src)	Constructs a InputStreamForwardSeekableStream from a regular InputStream.

Method Summary

Modifier and Type	Method	Description
int	available()	Forwards the request to the real InputStream.
boolean	canSeekBackwards()	Returns false since seking backwards is not supported.
void	close()	Forwards the request to the real InputStream.
long	getFilePointer()	Returns the current position in the stream (bytes read).
void	mark(int readLimit)	Forwards the request to the real InputStream.
boolean	markSupported()	Forwards the request to the real InputStream.
int	read()	Forwards the request to the real InputStream.
int	read(byte[] b, int off, int len)	Forwards the request to the real InputStream.
void	reset()	Forwards the request to the real InputStream.
void	seek(long pos)	Seeks forward to the given position in the stream.
long	skip(long n)	Forwards the request to the real InputStream.

Methods inherited from class org.apache.xmlgraphics.image.codec.util.SeekableStream

finalize, readBoolean, readByte, readChar, readCharLE, readDouble, readDoubleLE, readFloat, readFloatLE, readFully, readFully, readInt, readIntLE, readLine, readLong, readLongLE, readShort, readShortLE, readUnsignedByte, readUnsignedInt, readUnsignedIntLE, readUnsignedShort, readUnsignedShortLE, readUTF, skipBytes, wrapInputStream

Methods inherited from class java.io.InputStream

nullInputStream, read, readAllBytes, readNBytes, readNBytes, transferTo

Methods inherited from class java.lang.Object

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

Constructor Detail

ForwardSeekableStream

public ForwardSeekableStream(InputStream src)

Constructs a InputStreamForwardSeekableStream from a regular InputStream.

Method Detail

read

public final int read()
               throws IOException

Forwards the request to the real InputStream.

Specified by:

read in class SeekableStream

Returns:

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

Throws:

IOException - if an I/O error occurs.

read

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

Forwards the request to the real InputStream.

Specified by:

read in class SeekableStream

Parameters:

b - the buffer into which the data is read.

off - the start offset in array b at which the data is 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 I/O error occurs.

skip

public final long skip(long n)
                throws IOException

Forwards the request to the real InputStream.

Overrides:

skip in class InputStream

Throws:

IOException

available

public final int available()
                    throws IOException

Forwards the request to the real InputStream.

Overrides:

available in class InputStream

Throws:

IOException

close

public final void close()
                 throws IOException

Forwards the request to the real InputStream.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

Throws:

IOException

mark

public final void mark(int readLimit)

Forwards the request to the real InputStream. We use SeekableStream.markPos

Overrides:

mark in class SeekableStream

reset

public final void reset()
                 throws IOException

Forwards the request to the real InputStream. We use SeekableStream.markPos

Overrides:

reset in class SeekableStream

Throws:

IOException

markSupported

public boolean markSupported()

Forwards the request to the real InputStream.

Overrides:

markSupported in class SeekableStream

canSeekBackwards

public final boolean canSeekBackwards()

Returns false since seking backwards is not supported.

Overrides:

canSeekBackwards in class SeekableStream

getFilePointer

public final long getFilePointer()

Returns the current position in the stream (bytes read).

Specified by:

getFilePointer in class SeekableStream

Returns:

the offset from the beginning of the stream, in bytes, at which the next read occurs.

seek

public final void seek(long pos)
                throws IOException

Seeks forward to the given position in the stream. If pos is smaller than the current position as returned by getFilePointer(), nothing happens.

Specified by:

seek in class SeekableStream

Parameters:

pos - the offset position, measured in bytes from the beginning of the stream, at which to set the stream pointer.

Throws:

IOException - if pos is less than 0 or if an I/O error occurs.