java.io

Class OutputStream

java.lang.Object

java.io.OutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

Direct Known Subclasses:

ByteArrayOutputStream, FilterOutputStream

public abstract class OutputStream
extends Object
implements Closeable, Flushable

A writable sink for bytes.

Most clients will use output streams that write data to the file system (FileOutputStream), the network (Socket.getOutputStream()/URLConnection.getOutputStream()), or to an in-memory byte array (ByteArrayOutputStream).

Use OutputStreamWriter to adapt a byte stream like this one into a character stream.

Most clients should wrap their output stream with BufferedOutputStream. Callers that do only bulk writes may omit buffering.

Subclassing OutputStream

Subclasses that decorate another output stream should consider subclassing FilterOutputStream, which delegates all calls to the target output stream.

All output stream subclasses should override both write(int) and write(byte[],int,int). The three argument overload is necessary for bulk access to the data. This is much more efficient than byte-by-byte access.

See Also:

The implementation provided by this class behaves as described in the Java API documentation except for {@link write(int)} which throws an exception of type {@link java.lang.UnsupportedOperationException} instead of being abstract.

Constructor Summary

Constructors

Constructor and Description
OutputStream() Default constructor.

Method Summary

Modifier and Type	Method and Description
void	close() Closes this stream.
void	flush() Flushes this stream.
void	write(byte[] buffer) Equivalent to write(buffer, 0, buffer.length).
void	write(byte[] buffer, int offset, int count) Writes count bytes from the byte array buffer starting at position offset to this stream.
abstract void	write(int oneByte) Writes a single byte to this stream.

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, toString

Constructor Detail

OutputStream

public OutputStream()

Default constructor.

Method Detail

close

public void close()
           throws IOException

Closes this stream. Implementations of this method should free any resources used by the stream. This implementation does nothing.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException - if an error occurs while closing this stream.

flush

public void flush()
           throws IOException

Flushes this stream. Implementations of this method should ensure that any buffered data is written out. This implementation does nothing.

Specified by:

flush in interface Flushable

Throws:

IOException - if an error occurs while flushing this stream.

write

public void write(byte[] buffer)
           throws IOException

Equivalent to write(buffer, 0, buffer.length).

Throws:

IOException

write

public void write(byte[] buffer,
                  int offset,
                  int count)
           throws IOException

Writes count bytes from the byte array buffer starting at position offset to this stream.

Parameters:

buffer - the buffer to be written.

offset - the start position in buffer from where to get bytes.

count - the number of bytes from buffer to write to this stream.

Throws:

IOException - if an error occurs while writing to this stream.

IndexOutOfBoundsException - if offset < 0 or count < 0, or if offset + count is bigger than the length of buffer.

write

public abstract void write(int oneByte)
                    throws IOException

Writes a single byte to this stream. Only the least significant byte of the integer oneByte is written to the stream.

Parameters:

oneByte - the byte to be written.

Throws:

IOException - if an error occurs while writing to this stream.