Package java.io

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Class FilterOutputStream

public  class  java.io.FilterOutputStream
    extends  java.io.OutputStream  
{

        // Fields	 
    protected OutputStream out;	

        // Constructors
    public FilterOutputStream(OutputStream  out);	

        // Methods
    public void close();	
    public void flush();	
    public void write(byte  b[]);	
    public void write(byte  b[], int  off, int  len);	
    public void write(int  b);	
}

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), but provide 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.

Fields

out

protected OutputStream out 

The underlying output stream.

Constructors

FilterOutputStream

public FilterOutputStream(OutputStream  out) 

Creates an output stream filter built on top of the specified underlying output stream.

Parameter	Description
out	the underlying output stream

Methods

close

public void close() 

throws IOException 

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 .

Throw:

IOException

If an I/O error occurs.

Overrides:

close in class OutputStream .

flush

public void flush() 

throws IOException 

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 it underlying output stream .

Throw:

IOException

If an I/O error occurs.

Overrides:

flush in class OutputStream .

write

public void write(byte  b[]) 

throws IOException 

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.

Parameter	Description
b	the data to be written

Throw:

IOException

If an I/O error occurs.

Overrides:

write in class OutputStream .

write

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

throws IOException 

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.

Parameter	Description
b	the data
off	the start offset in the data
len	the number of bytes to write

Throw:

IOException

If an I/O error occurs.

Overrides:

write in class OutputStream .

write

public void write(int  b) 

throws IOException 

Writes the specified byte to this output stream.

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

Parameter	Description
b	the byte

Throw:

IOException

If an I/O error occurs.

Overrides:

write in class OutputStream .