org.apache.hadoop.hbase.io

Class ByteBufferWriterOutputStream

java.lang.Object

java.io.OutputStream

org.apache.hadoop.hbase.io.ByteBufferWriterOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable, ByteBufferWriter

@InterfaceAudience.Private
public class ByteBufferWriterOutputStream
extends OutputStream
implements ByteBufferWriter

When deal with OutputStream which is not ByteBufferWriter type, wrap it with this class. We will have to write offheap ByteBuffer (DBB) data into the OS. This class is having a temp byte array to which we can copy the DBB data for writing to the OS.
This is used while writing Cell data to WAL. In case of AsyncWAL, the OS created there is ByteBufferWriter. But in case of FSHLog, the OS passed by DFS client, is not of type ByteBufferWriter. We will need this temp solution until DFS client supports writing ByteBuffer directly to the OS it creates.
Note: This class is not thread safe.

Field Summary

Fields

Modifier and Type	Field and Description
private OutputStream	os
private static int	TEMP_BUF_LENGTH
private byte[]	tempBuf

Constructor Summary

Constructors

Constructor and Description
ByteBufferWriterOutputStream(OutputStream os)

Method Summary

Modifier and Type	Method and Description
void	close()
void	flush()
void	write(byte[] b, int off, int len)
void	write(ByteBuffer b, int off, int len) Writes len bytes from the specified ByteBuffer starting at offset off
void	write(int b)
void	writeInt(int i) Writes an int to the underlying output stream as four bytes, high byte first.

Methods inherited from class java.io.OutputStream

write

Methods inherited from class java.lang.Object

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

Field Detail

TEMP_BUF_LENGTH

private static final int TEMP_BUF_LENGTH

See Also:

Constant Field Values

os

private final OutputStream os

tempBuf

private byte[] tempBuf

Constructor Detail

ByteBufferWriterOutputStream

public ByteBufferWriterOutputStream(OutputStream os)

Method Detail

write

public void write(ByteBuffer b,
                  int off,
                  int len)
           throws IOException

Description copied from interface: ByteBufferWriter

Writes len bytes from the specified ByteBuffer starting at offset off

Specified by:

write in interface ByteBufferWriter

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.

writeInt

public void writeInt(int i)
              throws IOException

Description copied from interface: ByteBufferWriter

Writes an int to the underlying output stream as four bytes, high byte first.

Specified by:

writeInt in interface ByteBufferWriter

Parameters:

i - the int to write

Throws:

IOException - if an I/O error occurs.

write

public void write(int b)
           throws IOException

Specified by:

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

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class OutputStream

Throws:

IOException