edu.utah.janosvm.kit.comm.commspace
Class CommSpace

java.lang.Object
  |
  +--edu.utah.janosvm.sys.Exportable
        |
        +--edu.utah.janosvm.kit.comm.commspace.CommSpace

All Implemented Interfaces:

TemporaryExport

class CommSpace

extends Exportable

implements TemporaryExport

Variation on an array, with some tuple-space like properties. Objects are not shared between flows, they are copied on read.

Author:

Janos Ministry of Development

Field Summary

private CommSpaceElement[]

table The table mapping indicies to elements.

Fields inherited from class edu.utah.janosvm.sys.Exportable

anonManager, owner

Constructor Summary

(package private)

CommSpace(int size)

Method Summary

private void	checkIndex(int index)
boolean	expired() This method is called when there are no more imports for the export.
java.lang.Object	getName() Used to determine the name of this TemporaryObject object during revocation.
private void	notifyOnIndex(int index) Notify potential interested parties about a change at the given index.
(package private) CommSpaceElement	read(int index)
(package private) int	size()
(package private) CommSpaceElement	swap(int index, CommSpaceElement elem)
(package private) CommSpaceElement	take(int index)
java.lang.String	toString()
private void	waitOnIndex(int index) Wait for something to change in the slot at the given index.
(package private) CommSpaceElement	waitToTake(int index)
(package private) void	write(int index, CommSpaceElement elem) Write the given element at the given index.

Methods inherited from class edu.utah.janosvm.sys.Exportable

getAnonymousManager, pushOwnerReservation, returnFromOwner, setAnonymousManager, switchToOwner

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait, wait0

Field Detail

table

private final CommSpaceElement[] table

The table mapping indicies to elements.

Constructor Detail

CommSpace

CommSpace(int size)

Parameters:

size - The size of CommSpace to construct.

Method Detail

getName

public java.lang.Object getName()

Description copied from interface: TemporaryExport

Used to determine the name of this TemporaryObject object during revocation. Should return null for an anonymous export.

Specified by:

getName in interface TemporaryExport

size

final int size()

Returns:

The size of the CommSpace.

checkIndex

private final void checkIndex(int index)

Parameters:

index - Index to verify that it is within the bounds of the space.

Throws:

java.lang.ArrayIndexOutOfBoundsException - when the index is not valid.

write

void write(int index,
           CommSpaceElement elem)
     throws java.lang.ArrayIndexOutOfBoundsException

Write the given element at the given index.

take

CommSpaceElement take(int index)
                throws java.lang.ArrayIndexOutOfBoundsException

waitToTake

CommSpaceElement waitToTake(int index)
                      throws java.lang.ArrayIndexOutOfBoundsException,
                             java.lang.InterruptedException

read

CommSpaceElement read(int index)
                throws java.lang.ArrayIndexOutOfBoundsException

swap

CommSpaceElement swap(int index,
                      CommSpaceElement elem)

notifyOnIndex

private void notifyOnIndex(int index)

Notify potential interested parties about a change at the given index.

waitOnIndex

private void waitOnIndex(int index)
                  throws java.lang.InterruptedException

Wait for something to change in the slot at the given index.

expired

public boolean expired()

Description copied from interface: TemporaryExport

This method is called when there are no more imports for the export. If it returns true than the export is revoked otherwise it will continue to be available for importing.

Specified by:

expired in interface TemporaryExport

Following copied from interface: edu.utah.janosvm.sys.TemporaryExport

Returns:

True if the export has expired and should be revoked.

toString

public java.lang.String toString()

Overrides:

toString in class Exportable