Class FilterOutputStream
- java.lang.Object
-
- java.io.OutputStream
-
- java.io.FilterOutputStream
- All Implemented Interfaces:
-
Closeable
,Flushable
,AutoCloseable
- Direct Known Subclasses:
-
BufferedOutputStream
,CheckedOutputStream
,CipherOutputStream
,DataOutputStream
,DeflaterOutputStream
,DigestOutputStream
,InflaterOutputStream
,PrintStream
public class FilterOutputStream extends 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 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.
- Since:
- 1.0
Field Summary
Modifier and Type | Field | Description |
---|---|---|
protected OutputStream | out | The underlying output stream to be filtered. |
Constructor Summary
Constructor | Description |
---|---|
FilterOutputStream(OutputStream out) | Creates an output stream filter built on top of the specified underlying output stream. |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
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) | Writes |
void | write(byte[] b,
int off,
int len) | Writes |
void | write(int b) | Writes the specified |
Methods declared in class java.io.OutputStream
nullOutputStream
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Field Detail
out
protected OutputStream out
The underlying output stream to be filtered.
Constructor Detail
FilterOutputStream
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 fieldthis.out
for later use, ornull
if this instance is to be created without an underlying stream.
Method Detail
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, that is, it performs out.write(b)
.
Implements the abstract write
method of OutputStream
.
- Specified by:
-
write
in classOutputStream
- Parameters:
-
b
- thebyte
. - Throws:
-
IOException
- if an I/O error occurs.
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 output stream with the single argument b
.
- Overrides:
-
write
in classOutputStream
- Parameters:
-
b
- the data to be written. - Throws:
-
IOException
- if an I/O error occurs. - See Also:
write(byte[], int, int)
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 output stream with the same arguments. Subclasses of FilterOutputStream
should provide a more efficient implementation of this method.
- Overrides:
-
write
in classOutputStream
- 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:
write(int)
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 its underlying output stream.
- Specified by:
-
flush
in interfaceFlushable
- Overrides:
-
flush
in classOutputStream
- Throws:
-
IOException
- if an I/O error occurs. - See Also:
out
close
public void close() throws IOException
Closes this output stream and releases any system resources associated with the stream.
When not already closed, the close
method of
FilterOutputStream
calls its flush
method, and then calls the close
method of its underlying output stream.
- Specified by:
-
close
in interfaceAutoCloseable
- Specified by:
-
close
in interfaceCloseable
- Overrides:
-
close
in classOutputStream
- Throws:
-
IOException
- if an I/O error occurs. - See Also:
-
flush()
,out