java.beans.PropertyChangeEvent Maven / Gradle / Ivy
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package java.beans;
/**
* 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.
*/
public class PropertyChangeEvent extends java.util.EventObject {
private static final long serialVersionUID = 7042693688939648123L;
/**
* Constructs a new PropertyChangeEvent.
*
* @param source The bean that fired the event.
* @param propertyName The programmatic name of the property
* that was changed.
* @param oldValue The old value of the property.
* @param newValue The new value of the property.
*/
public PropertyChangeEvent(Object source, String propertyName,
Object oldValue, Object newValue) {
super(source);
this.propertyName = propertyName;
this.newValue = newValue;
this.oldValue = oldValue;
}
/**
* Gets the programmatic name of the property that was changed.
*
* @return The programmatic name of the property that was changed.
* May be null if multiple properties have changed.
*/
public String getPropertyName() {
return propertyName;
}
/**
* Gets the new value for the property, expressed as an Object.
*
* @return The new value for the property, expressed as an Object.
* May be null if multiple properties have changed.
*/
public Object getNewValue() {
return newValue;
}
/**
* Gets the old value for the property, expressed as an Object.
*
* @return The old value for the property, expressed as an Object.
* May be null if multiple properties have changed.
*/
public Object getOldValue() {
return oldValue;
}
/**
* Sets the propagationId object for the event.
*
* @param propagationId The propagationId object for the event.
*/
public void setPropagationId(Object propagationId) {
this.propagationId = 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.
*
* @return the propagationId object associated with a bound/constrained
* property update.
*/
public Object getPropagationId() {
return propagationId;
}
/**
* name of the property that changed. May be null, if not known.
* @serial
*/
private String propertyName;
/**
* New value for property. May be null if not known.
* @serial
*/
private Object newValue;
/**
* Previous value for property. May be null if not known.
* @serial
*/
private Object oldValue;
/**
* Propagation ID. May be null.
* @serial
* @see #getPropagationId
*/
private Object propagationId;
/**
* Returns a string representation of the object.
*
* @return a string representation of the object
*
* @since 1.7
*/
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();
}
void appendTo(StringBuilder sb) {
}
}