public class

FilterOutputStream

extends OutputStream
java.lang.Object
   ↳ java.io.OutputStream
     ↳ java.io.FilterOutputStream
Known Direct Subclasses
Known Indirect Subclasses

Class Overview

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

Summary

Fields
protected OutputStream out The underlying output stream to be filtered.
Public Constructors
FilterOutputStream(OutputStream out)
Creates an output stream filter built on top of the specified underlying output stream.
Public Methods
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.
void write(byte[] b, int off, int len)
Writes len bytes from the specified byte array starting at offset off to this output stream.
void write(byte[] b)
Writes b.length bytes to this output stream.
void write(int b)
Writes the specified byte to this output stream.
[Expand]
Inherited Methods
From class java.io.OutputStream
From class java.lang.Object
From interface java.io.Closeable
From interface java.io.Flushable

Fields

protected OutputStream out

The underlying output stream to be filtered.

Public Constructors

public FilterOutputStream (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.

Public Methods

public void close ()

Closes this output stream and releases any system resources associated with the stream.

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

Throws
IOException if an I/O error occurs.
See Also

public void flush ()

Flushes this output stream and forces any buffered output bytes to be written out to the stream.

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

Throws
IOException if an I/O error occurs.
See Also

public void write (byte[] b, int off, int len)

Writes len bytes from the specified byte array starting at offset off to this output stream.

The write method of FilterOutputStream calls the write method of one argument on each byte to output.

Note that this method does not call the write method of its underlying input stream with the same arguments. Subclasses of FilterOutputStream should provide a more efficient implementation of this method.

Parameters
b the data.
off the start offset in the data.
len the number of bytes to write.
Throws
IOException if an I/O error occurs.
See Also

public void write (byte[] b)

Writes b.length bytes to this output stream.

The write method of FilterOutputStream calls its write method of three arguments with the arguments b, 0, and b.length.

Note that this method does not call the one-argument write method of its underlying stream with the single argument b.

Parameters
b the data to be written.
Throws
IOException if an I/O error occurs.
See Also

public void write (int b)

Writes the specified byte to this output stream.

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

Implements the abstract write method of OutputStream.

Parameters
b the byte.
Throws
IOException if an I/O error occurs.