net.sf.kdgcommons.io

Class MonitoredInputStream

java.lang.Object

java.io.InputStream

net.sf.kdgcommons.io.MonitoredInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class MonitoredInputStream
extends InputStream

A decorator InputStream that invokes a progress(long, long) method after each read, reporting the number of bytes processed. Applications can subclass and override this method to provide features such as a progress bar.

Constructor Summary

Constructors

Constructor and Description
MonitoredInputStream(InputStream delegate)

Method Summary

Modifier and Type	Method and Description
int	available() Returns the number of bytes available from the underlying stream.
void	close() Closes the underlying stream.
void	mark(int readlimit) Sets a mark on the underlying stream.
boolean	markSupported() Returns whether the underlying stream supports mark(int).
void	progress(long lastRead, long totalBytes) Called after each operation that reads bytes, to report the number of bytes read.
int	read() Reads a single byte from the underlying stream, blocking if necessary.
int	read(byte[] b) Reads up bytes from the underlying stream into the passed buffer, blocking if necessary.
int	read(byte[] b, int off, int len) Reads up to the specified number of bytes from the underlying stream, blocking if necessary.
void	reset() Resets the underlying stream to a previous mark.
long	skip(long n) Skips up to a specified number of bytes in the underlying stream.

Methods inherited from class java.lang.Object

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

Constructor Detail

MonitoredInputStream

public MonitoredInputStream(InputStream delegate)

Method Detail

available

public int available()
              throws IOException

Returns the number of bytes available from the underlying stream. Has no effect on monitoring.

Overrides:

available in class InputStream

Throws:

IOException

close

public void close()
           throws IOException

Closes the underlying stream.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class InputStream

Throws:

IOException

read

public int read()
         throws IOException

Reads a single byte from the underlying stream, blocking if necessary. Calls progress(long, long) after the byte has been read, reporting either 1 or 0 (depending on whether the stream is at its end).

Specified by:

read in class InputStream

Throws:

IOException

read

public int read(byte[] b)
         throws IOException

Reads up bytes from the underlying stream into the passed buffer, blocking if necessary. Calls progress(long, long) after the read completes, reporting the actual number of bytes read.

Overrides:

read in class InputStream

Throws:

IOException

read

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

Reads up to the specified number of bytes from the underlying stream, blocking if necessary. Calls progress(long, long) after the read completes, reporting the actual number of bytes read.

Overrides:

read in class InputStream

Throws:

IOException

markSupported

public boolean markSupported()

Returns whether the underlying stream supports mark(int).

Overrides:

markSupported in class InputStream

mark

public void mark(int readlimit)

Sets a mark on the underlying stream.

Overrides:

mark in class InputStream

reset

public void reset()
           throws IOException

Resets the underlying stream to a previous mark. Does not reset the monitoring counts; these will show total number of bytes read.

Overrides:

reset in class InputStream

Throws:

IOException

skip

public long skip(long n)
          throws IOException

Skips up to a specified number of bytes in the underlying stream. Will call progress(long, long) after the skip completes, with the number of bytes skipped.

Overrides:

skip in class InputStream

Throws:

IOException

progress

public void progress(long lastRead,
                     long totalBytes)

Called after each operation that reads bytes, to report the number of bytes read. The default implementation of this method is a no-op.

Parameters:

lastRead - Number of bytes in last read operation. Note that this may be 0.

totalBytes - Total number of bytes read or skipped since this class was instantiated.