com.sun.jini.mercury

Class LogOutputStream

java.lang.Object

java.io.OutputStream

com.sun.jini.mercury.LogOutputStream

All Implemented Interfaces:

LogStream, Closeable, Flushable, AutoCloseable

 class LogOutputStream
extends OutputStream
implements LogStream

This class implements the interface for interacting with output log streams. It extends java.util.OutputStream and overrides its methods in order to provide buffered output as well as byte offset tracking, which is useful during recovery situations. The additional methods drain and sync allow for the flushing of any buffered data and synchronizing data buffers with the underlying device, respectively.

Since:

1.1

Author:

Sun Microsystems, Inc.

Field Summary

Fields

Modifier and Type	Field and Description
private byte[]	buf byte array buffer for written data
private static int	BUFSIZE Holds value of the internal buffer size to allocate
private StreamKey	key Associated key for this stream object
private long	offset cumulative index/offset into this stream
private FileOutputStream	out Underlying output stream from which bytes are written
private int	pos index/offset into the internal write buffer

Constructor Summary

Constructors

Constructor and Description
LogOutputStream(File file, StreamKey key, boolean append) Simple constructor that accepts a File, StreamKey and boolean arguments.

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Closes this LogStream object and releases any associated resources.
(package private) void	drain() Writes any unwritten bytes to the underlying output stream.
void	flush()
Object	getKey() Returns the associated key for this LogStream.
(package private) long	getOffset() Returns the current "write" offset into this stream object.
(package private) void	sync() Synchronizes system buffers with underlying device.
void	write(byte[] b)
void	write(byte[] b, int off, int len)
void	write(int b)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

BUFSIZE

private static final int BUFSIZE

Holds value of the internal buffer size to allocate

See Also:

Constant Field Values

buf

private byte[] buf

byte array buffer for written data

pos

private int pos

index/offset into the internal write buffer

offset

private long offset

cumulative index/offset into this stream

out

private FileOutputStream out

Underlying output stream from which bytes are written

key

private StreamKey key

Associated key for this stream object

Constructor Detail

LogOutputStream

public LogOutputStream(File file,
               StreamKey key,
               boolean append)
                throws FileNotFoundException

Simple constructor that accepts a File, StreamKey and boolean arguments. The File and StreamKey arguments are assigned to their respective internal fields. The boolean argument is used to determine whether or not to append bytes to the underlying (file) output stream.

Parameters:

file - the File to used

key - the associated key for this object

append - determines whether or not to append to the underlying stream

Throws:

IllegalArgumentException - if either the file or key argument is null

FileNotFoundException - if the file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason

Method Detail

write

public void write(int b)
           throws IOException

Specified by:

write in class OutputStream

Throws:

IOException

write

public void write(byte[] b)
           throws IOException

Overrides:

write in class OutputStream

Throws:

IOException

write

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

Overrides:

write in class OutputStream

Throws:

IOException

flush

public void flush()
           throws IOException

Specified by:

flush in interface Flushable

Overrides:

flush in class OutputStream

Throws:

IOException

close

public void close()
           throws IOException

Description copied from interface: LogStream

Closes this LogStream object and releases any associated resources.

Specified by:

close in interface LogStream

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class OutputStream

Throws:

IOException - if an I/O error occured while attempting to close the LogStream.

getOffset

long getOffset()

Returns the current "write" offset into this stream object.

sync

void sync()
    throws IOException,
           SyncFailedException

Synchronizes system buffers with underlying device.

Throws:

IOException - if an I/O error occurs

SyncFailedException - if the buffers cannot be guaranteed to have synchronized with physical media

drain

void drain()
     throws IOException

Writes any unwritten bytes to the underlying output stream.

Throws:

IOException - if an I/O error occurs

getKey

public Object getKey()

Description copied from interface: LogStream

Returns the associated key for this LogStream. This key is intended to be used as the key in a java.util.Collection.

Specified by:

getKey in interface LogStream