java.beans
public class: PropertyChangeEvent [javadoc |
source]
java.lang.Object
java.util.EventObject
java.beans.PropertyChangeEvent
All Implemented Interfaces:
Serializable
Direct Known Subclasses:
IndexedPropertyChangeEvent
A "PropertyChange" event gets delivered whenever a bean changes a "bound"
or "constrained" property. A PropertyChangeEvent object is sent as an
argument to the PropertyChangeListener and VetoableChangeListener methods.
Normally PropertyChangeEvents are accompanied by the name and the old
and new value of the changed property. If the new value is a primitive
type (such as int or boolean) it must be wrapped as the
corresponding java.lang.* Object type (such as Integer or Boolean).
Null values may be provided for the old and the new values if their
true values are not known.
An event source may send a null object as the name to indicate that an
arbitrary set of if its properties have changed. In this case the
old and new values should also be null.
Constructor: |
public PropertyChangeEvent(Object source,
String propertyName,
Object oldValue,
Object newValue) {
super(source);
this.propertyName = propertyName;
this.newValue = newValue;
this.oldValue = oldValue;
}
Constructs a new PropertyChangeEvent . Parameters:
source - The bean that fired the event.
propertyName - The programmatic name of the property
that was changed.
oldValue - The old value of the property.
newValue - The new value of the property.
|
Methods from java.lang.Object: |
---|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Method from java.beans.PropertyChangeEvent Detail: |
void appendTo(StringBuilder sb) {
}
|
public Object getNewValue() {
return newValue;
}
Gets the new value for the property, expressed as an Object. |
public Object getOldValue() {
return oldValue;
}
Gets the old value for the property, expressed as an Object. |
public Object getPropagationId() {
return propagationId;
}
The "propagationId" field is reserved for future use. In Beans 1.0
the sole requirement is that if a listener catches a PropertyChangeEvent
and then fires a PropertyChangeEvent of its own, then it should
make sure that it propagates the propagationId field from its
incoming event to its outgoing event. |
public String getPropertyName() {
return propertyName;
}
Gets the programmatic name of the property that was changed. |
public void setPropagationId(Object propagationId) {
this.propagationId = propagationId;
}
Sets the propagationId object for the event. |
public String toString() {
StringBuilder sb = new StringBuilder(getClass().getName());
sb.append("[propertyName=").append(getPropertyName());
appendTo(sb);
sb.append("; oldValue=").append(getOldValue());
sb.append("; newValue=").append(getNewValue());
sb.append("; propagationId=").append(getPropagationId());
sb.append("; source=").append(getSource());
return sb.append("]").toString();
}
Returns a string representation of the object. |