org.eclipse.net4j.util.io
Class DelegatingOutputStream

java.lang.Object
  extended by java.io.OutputStream
      extended by org.eclipse.net4j.util.io.DelegatingOutputStream
All Implemented Interfaces:
java.io.Closeable, java.io.Flushable
Direct Known Subclasses:
XOROutputStream

public class DelegatingOutputStream
extends java.io.OutputStream

This class is the superclass of all classes that filter output streams. These streams sit on top of an already existing output stream (the underlying output stream) which it uses as its basic sink of data, but possibly transforming the data along the way or providing additional functionality.

The class DelegatingOutputStream itself simply overrides all methods of OutputStream with versions that pass all requests to the underlying output stream. Subclasses of DelegatingOutputStream may further override some of these methods as well as provide additional methods and fields.

Note: The only difference to FilterOutputStream is that DelegatingOutputStream does not override OutputStream.write(byte[]) or OutputStream.write(byte[], int, int) but rather exposes the original implementations of InputStream which call write(int) instead of their delegate counterparts.


Field Summary
protected  java.io.OutputStream out
          The underlying output stream to be filtered.
 
Constructor Summary
DelegatingOutputStream(java.io.OutputStream out)
          Creates an output stream filter built on top of the specified underlying output stream.
 
Method Summary
 void close()
          Closes this output stream and releases any system resources associated with the stream.
 void flush()
          Flushes this output stream and forces any buffered output bytes to be written out to the stream.
 java.io.OutputStream getDelegate()
           
 void write(int b)
          Writes the specified byte to this output stream.
 
Methods inherited from class java.io.OutputStream
write, write
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

out

protected java.io.OutputStream out
The underlying output stream to be filtered.

Constructor Detail

DelegatingOutputStream

public DelegatingOutputStream(java.io.OutputStream out)
Creates an output stream filter built on top of the specified underlying output stream.

Parameters:
out - the underlying output stream to be assigned to the field this.out for later use, or null if this instance is to be created without an underlying stream.
Method Detail

getDelegate

public java.io.OutputStream getDelegate()

write

public void write(int b)
           throws java.io.IOException
Writes the specified byte to this output stream.

The write method of DelegatingOutputStream calls the write method of its underlying output stream, that is, it performs out.write(b).

Implements the abstract write method of OutputStream.

Specified by:
write in class java.io.OutputStream
Parameters:
b - the byte.
Throws:
java.io.IOException - if an I/O error occurs.

flush

public void flush()
           throws java.io.IOException
Flushes this output stream and forces any buffered output bytes to be written out to the stream.

The flush method of DelegatingOutputStream calls the flush method of its underlying output stream.

Specified by:
flush in interface java.io.Flushable
Overrides:
flush in class java.io.OutputStream
Throws:
java.io.IOException - if an I/O error occurs.
See Also:
out

close

public void close()
           throws java.io.IOException
Closes this output stream and releases any system resources associated with the stream.

The close method of DelegatingOutputStream calls its flush method, and then calls the close method of its underlying output stream.

Specified by:
close in interface java.io.Closeable
Overrides:
close in class java.io.OutputStream
Throws:
java.io.IOException - if an I/O error occurs.
See Also:
flush(), out

Copyright (c) 2004 - 2008 Eike Stepper, Germany.
All Rights Reserved.