uk.org.ogsadai.common.properties
Class SelfUpdatingProperty

java.lang.Object
  |
  +--java.util.Observable
        |
        +--uk.org.ogsadai.common.properties.Property
              |
              +--uk.org.ogsadai.common.properties.SelfUpdatingProperty

public class SelfUpdatingProperty

extends Property

A property that updates its value automatically whenever a specified object changes state.

The specified object is Observable The new property value will be the argument passed to the notifyObservers method of the Observable object. This in turn will be passed to the observers of this property.

Author:

The OGSA-DAI Project Team

Field Summary

private static java.lang.String	COPYRIGHT_NOTICE
private java.util.Observable	mObservable
private java.lang.Object	mValue

Fields inherited from class uk.org.ogsadai.common.properties.Property

mName, mSecurityContext

Fields inherited from class java.util.Observable

Constructor Summary

SelfUpdatingProperty(javax.xml.namespace.QName name, java.lang.Object initialValue, java.util.Observable observable)
Create a new property with the specified name and initial value.

Method Summary

protected java.util.Observer	createObserver() Creates and returns an observer that will automatically notify observers of the property whenever the property value changes state.
java.lang.Object	getValue() Return the property value.
void	setValue(java.lang.Object value) Set the property value.

Methods inherited from class uk.org.ogsadai.common.properties.Property

getName, setName, setSecurityContext

Methods inherited from class java.util.Observable

addObserver, clearChanged, countObservers, deleteObserver, deleteObservers, hasChanged, notifyObservers, notifyObservers, setChanged

Methods inherited from class java.lang.Object

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

Field Detail

COPYRIGHT_NOTICE

private static final java.lang.String COPYRIGHT_NOTICE

See Also:

Constant Field Values

mValue

private java.lang.Object mValue

mObservable

private final java.util.Observable mObservable

Constructor Detail

SelfUpdatingProperty

public SelfUpdatingProperty(javax.xml.namespace.QName name,
                            java.lang.Object initialValue,
                            java.util.Observable observable)

Create a new property with the specified name and initial value. The value will be updated whenever the specified observable object notifies its observers of a change of state.

Parameters:

name - The name of the property.

initialValue - The initial value for the property.

observable - The observable object that will govern when the property value is updated.

Method Detail

createObserver

protected java.util.Observer createObserver()

Creates and returns an observer that will automatically notify observers of the property whenever the property value changes state.

Returns:

observer.

getValue

public java.lang.Object getValue()
                          throws PropertyValueException

Description copied from class: Property

Return the property value.

Specified by:

getValue in class Property

Returns:

the value for the property or null if it has not been set.

Throws:

PropertyValueException - if an error occurs when obtaining the value.

setValue

public void setValue(java.lang.Object value)

Description copied from class: Property

Set the property value.

Specified by:

setValue in class Property

Parameters:

value - Property value.