Package org.apache.sysds.runtime.util

Class FastBufferedDataOutputStream

java.lang.Object

java.io.OutputStream

java.io.FilterOutputStream

org.apache.sysds.runtime.util.FastBufferedDataOutputStream

All Implemented Interfaces:

Closeable, DataOutput, Flushable, AutoCloseable, MatrixBlockDataOutput

public class FastBufferedDataOutputStream
extends FilterOutputStream
implements DataOutput, MatrixBlockDataOutput

This buffered output stream is essentially a merged version of BufferedOutputStream and DataOutputStream, wrt SystemDS requirements. Micro-benchmarks showed a 25% performance improvement for local write binary block due to the following advantages: - 1) unsynchronized buffered output stream (not required in SystemDS since single writer) - 2) single output buffer (avoid two-level buffers of individual streams) - 3) specific support for writing double arrays in a blockwise fashion

Constructor Summary

Constructors

Constructor	Description
FastBufferedDataOutputStream(OutputStream out)
FastBufferedDataOutputStream(OutputStream out, int size)

Method Summary

Modifier and Type	Method	Description
void	close()
void	flush()
void	write(byte[] b, int off, int len)
void	write(int b)
void	writeBoolean(boolean v)
void	writeByte(int v)
void	writeBytes(String s)
void	writeChar(int v)
void	writeChars(String s)
void	writeDouble(double v)
void	writeDoubleArray(int len, double[] varr)	Writes the double array of a dense block to the data output.
void	writeFloat(float v)
void	writeInt(int v)
void	writeLong(long v)
void	writeShort(int v)
void	writeSparseRows(int rlen, SparseBlock rows)	Writes the sparse rows array of a sparse block to the data output.
void	writeUTF(String s)

Methods inherited from class java.io.FilterOutputStream

write

Methods inherited from class java.io.OutputStream

nullOutputStream

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.io.DataOutput

write

Constructor Detail

FastBufferedDataOutputStream

public FastBufferedDataOutputStream(OutputStream out)

FastBufferedDataOutputStream

public FastBufferedDataOutputStream(OutputStream out,
                                    int size)

Method Detail

write

public void write(int b)
           throws IOException

Specified by:

write in interface DataOutput

Overrides:

write in class FilterOutputStream

Throws:

IOException

write

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

Specified by:

write in interface DataOutput

Overrides:

write in class FilterOutputStream

Throws:

IOException

flush

public void flush()
           throws IOException

Specified by:

flush in interface Flushable

Overrides:

flush in class FilterOutputStream

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class FilterOutputStream

Throws:

IOException

writeBoolean

public void writeBoolean(boolean v)
                  throws IOException

Specified by:

writeBoolean in interface DataOutput

Throws:

IOException

writeInt

public void writeInt(int v)
              throws IOException

Specified by:

writeInt in interface DataOutput

Throws:

IOException

writeLong

public void writeLong(long v)
               throws IOException

Specified by:

writeLong in interface DataOutput

Throws:

IOException

writeDouble

public void writeDouble(double v)
                 throws IOException

Specified by:

writeDouble in interface DataOutput

Throws:

IOException

writeByte

public void writeByte(int v)
               throws IOException

Specified by:

writeByte in interface DataOutput

Throws:

IOException

writeShort

public void writeShort(int v)
                throws IOException

Specified by:

writeShort in interface DataOutput

Throws:

IOException

writeBytes

public void writeBytes(String s)
                throws IOException

Specified by:

writeBytes in interface DataOutput

Throws:

IOException

writeChar

public void writeChar(int v)
               throws IOException

Specified by:

writeChar in interface DataOutput

Throws:

IOException

writeChars

public void writeChars(String s)
                throws IOException

Specified by:

writeChars in interface DataOutput

Throws:

IOException

writeFloat

public void writeFloat(float v)
                throws IOException

Specified by:

writeFloat in interface DataOutput

Throws:

IOException

writeUTF

public void writeUTF(String s)
              throws IOException

Specified by:

writeUTF in interface DataOutput

Throws:

IOException

writeDoubleArray

public void writeDoubleArray(int len,
                             double[] varr)
                      throws IOException

Description copied from interface: MatrixBlockDataOutput

Writes the double array of a dense block to the data output.

Specified by:

writeDoubleArray in interface MatrixBlockDataOutput

Parameters:

len - ?

varr - ?

Throws:

IOException - if IOException occurs

writeSparseRows

public void writeSparseRows(int rlen,
                            SparseBlock rows)
                     throws IOException

Description copied from interface: MatrixBlockDataOutput

Writes the sparse rows array of a sparse block to the data output.

Specified by:

writeSparseRows in interface MatrixBlockDataOutput

Parameters:

rlen - ?

rows - sparse block

Throws:

IOException - if IOException occurs