public class

StreamGobbler

extends InputStream
java.lang.Object
   ↳ java.io.InputStream
     ↳ com.trilead.ssh2.StreamGobbler

Class Overview

A StreamGobbler is an InputStream that uses an internal worker thread to constantly consume input from another InputStream. It uses a buffer to store the consumed data. The buffer size is automatically adjusted, if needed.

This class is sometimes very convenient - if you wrap a session's STDOUT and STDERR InputStreams with instances of this class, then you don't have to bother about the shared window of STDOUT and STDERR in the low level SSH-2 protocol, since all arriving data will be immediatelly consumed by the worker threads. Also, as a side effect, the streams will be buffered (e.g., single byte read() operations are faster).

Other SSH for Java libraries include this functionality by default in their STDOUT and STDERR InputStream implementations, however, please be aware that this approach has also a downside:

If you do not call the StreamGobbler's read() method often enough and the peer is constantly sending huge amounts of data, then you will sooner or later encounter a low memory situation due to the aggregated data (well, it also depends on the Java heap size). Joe Average will like this class anyway - a paranoid programmer would never use such an approach.

The term "StreamGobbler" was taken from an article called "When Runtime.exec() won't", see http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html.

Summary

[Expand]
Inherited Constants
From class java.io.InputStream
Fields
private byte[] buffer
private IOException exception
private InputStream is
private boolean isClosed
private boolean isEOF
private int read_pos
private Object synchronizer
private StreamGobbler.GobblerThread t
private int write_pos
Public Constructors
StreamGobbler(InputStream is)
Public Methods
int available()
void close()
int read(byte[] b)
int read()
int read(byte[] b, int off, int len)
[Expand]
Inherited Methods
From class java.io.InputStream
From class java.lang.Object
From interface java.io.Closeable

Fields

private byte[] buffer

private IOException exception

private InputStream is

private boolean isClosed

private boolean isEOF

private int read_pos

private Object synchronizer

private StreamGobbler.GobblerThread t

private int write_pos

Public Constructors

public StreamGobbler (InputStream is)

Parameters
is

Public Methods

public int available ()

Throws
IOException

public void close ()

Throws
IOException

public int read (byte[] b)

Parameters
b
Throws
IOException

public int read ()

Throws
IOException

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

Parameters
b
off
len
Throws
IOException