org.trianacode.taskgraph.service

Class Monitor

java.lang.Object

org.trianacode.taskgraph.service.Monitor

All Implemented Interfaces:

java.io.Serializable, java.lang.Runnable

public class Monitor
extends java.lang.Object
implements java.lang.Runnable, java.io.Serializable

This class is used by the LocalCable class to ensure that all the information that is being sent out of a sending unit is being received by a receiving unit and visa-verse. It does this by using Java monitors to provide the necessary synchronization needed between the sending and receiving units within the the Triana system. There is one monitor set up for each connection (i.e. by using a GAPCable) made.

See Also:

LocalCable, Serialized Form

Constructor Summary

Constructors

Constructor and Description
Monitor(RunnableInstance sn)
Monitor(RunnableInstance sn, RunnableInstance rn, Node innode) Creates a new monitor for a particular connection name and a RunnableInstance object (i.e.

Method Summary

Methods

Modifier and Type	Method and Description
void	block(boolean put) Blocks until the unit is ready to receivd the data/the data is sent
void	empty() Flushes the data out of the pipes
void	finalize() When the garbage collector de-allocates space from this object we reset all references to other object we have used
java.lang.Object	get() The Receiving unit calls this method when it wants to receive data.
boolean	isReady() The Receiving unit calls this method when it wants to receive data which may or may not be there.
void	myNotify() Replaces the basic notifyAll fuction to keep a note of whether this monitor is being notified or released
void	put(java.lang.Object data) The Sending unit calls this method when it has data which is ready to be sent to the receiving unit.
void	putButDontBlock(java.lang.Object data) This puts the data on this connection but does not block the unit.
void	release() Makes the tempdata available by releasing the monitor and waking up the receiving unit.
void	run() Release the data to the receving task.

Methods inherited from class java.lang.Object

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

Constructor Detail

Monitor

public Monitor(RunnableInstance sn,
       RunnableInstance rn,
       Node innode)

Creates a new monitor for a particular connection name and a RunnableInstance object (i.e. a LocalCable).

Monitor

public Monitor(RunnableInstance sn)

Method Detail

put

public void put(java.lang.Object data)
         throws EmptyingException

The Sending unit calls this method when it has data which is ready to be sent to the receiving unit. The monitor then waits until the unit is ready to receive the data before releasing the data

Throws:

EmptyingException

putButDontBlock

public void putButDontBlock(java.lang.Object data)

This puts the data on this connection but does not block the unit. Instead it puts it in the background and waits in a separate thread

block

public void block(boolean put)
           throws EmptyingException

Blocks until the unit is ready to receivd the data/the data is sent

Throws:

EmptyingException

release

public void release()

Makes the tempdata available by releasing the monitor and waking up the receiving unit.

get

public java.lang.Object get()
                     throws EmptyingException

The Receiving unit calls this method when it wants to receive data. It then waits until it is notified that the data is ready to be received.

Throws:

EmptyingException

myNotify

public void myNotify()

Replaces the basic notifyAll fuction to keep a note of whether this monitor is being notified or released

run

public void run()

Release the data to the receving task.

Specified by:

run in interface java.lang.Runnable

empty

public void empty()

Flushes the data out of the pipes

isReady

public boolean isReady()

The Receiving unit calls this method when it wants to receive data which may or may not be there. If it is available then the unit returns true and then can go ahead and call the get() method to retrieve the date otherwise it return false. This method is used to implement the idea of an optional() connection within Triana e.g. if an input node is marked optional then the unit can quite happily process its information without contribution from this input i.e. the input does not block the unit. However if data is ready at the input then the unit can retrieve it and use it.

see RunnableUnit#optional

finalize

public void finalize()
              throws java.lang.Throwable

When the garbage collector de-allocates space from this object we reset all references to other object we have used

Overrides:

finalize in class java.lang.Object

Throws:

java.lang.Throwable