org.metasyntactic.thread
Class AlternatingReadersWritersMonitor

java.lang.Object
  |
  +--org.metasyntactic.thread.AlternatingReadersWritersMonitor

All Implemented Interfaces:

ReaderWriterMonitor

public class AlternatingReadersWritersMonitor

extends java.lang.Object

implements ReaderWriterMonitor

The Alternating-Readers/Writers Monitor will give the shared structure to a waiting writer when readers have finished with it and to readers when a writer has finished with it.

Field Summary

protected int	nextBatch Index in readersReadingAndWaiting of batch of number of readers waiting to read.
protected int[]	readersReadingAndWaiting Number readers reading and waiting to read in this batch or the next batch.
protected int	thisBatch Index in nr of batch of number of readers currently reading.
protected int	writersTotal Number of writers total.
protected int	writerWriting Number writers writing, 0 or 1

Constructor Summary

AlternatingReadersWritersMonitor()

Method Summary

void	startReading() Called to begin reading the shared data structure.
void	startWriting() Called to begin writing the shared data structure.
void	stopReading() Called when the thread is finished reading the shared data structure.
void	stopWriting() Called when the thread is finished writing the shared data structure.

Methods inherited from class java.lang.Object

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

Field Detail

thisBatch

protected int thisBatch

Index in nr of batch of number of readers currently reading.

nextBatch

protected int nextBatch

Index in readersReadingAndWaiting of batch of number of readers waiting to read. Always equal to 1-thisBatch.

readersReadingAndWaiting

protected int[] readersReadingAndWaiting

Number readers reading and waiting to read in this batch or the next batch.

writerWriting

protected int writerWriting

Number writers writing, 0 or 1

writersTotal

protected int writersTotal

Number of writers total.

Constructor Detail

AlternatingReadersWritersMonitor

public AlternatingReadersWritersMonitor()

Method Detail

startReading

public void startReading()
                  throws java.lang.InterruptedException

Description copied from interface: ReaderWriterMonitor

Called to begin reading the shared data structure. exception InterruptedException If interrupted while waiting for access.

Specified by:

startReading in interface ReaderWriterMonitor

Throws:

java.lang.InterruptedException - When the thread is interrupted before starting

stopReading

public void stopReading()

Description copied from interface: ReaderWriterMonitor

Called when the thread is finished reading the shared data structure.

Specified by:

stopReading in interface ReaderWriterMonitor

startWriting

public void startWriting()
                  throws java.lang.InterruptedException

Description copied from interface: ReaderWriterMonitor

Called to begin writing the shared data structure. exception InterruptedException If interrupted while waiting for access.

Specified by:

startWriting in interface ReaderWriterMonitor

Throws:

java.lang.InterruptedException - When the thread is interrupted before starting

stopWriting

public void stopWriting()

Description copied from interface: ReaderWriterMonitor

Called when the thread is finished writing the shared data structure.

Specified by:

stopWriting in interface ReaderWriterMonitor