/* EventObject.java -- represents an event on an object
Copyright (C) 1999, 2000, 2002, 2005 Free Software Foundation, Inc.
This file is part of GNU Classpath.
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permission to link this library with independent modules to produce an
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package java.util;
import java.io.Serializable;
/**
* Represents Events fired by Objects.
*
* @author Eric Blake (ebb9@email.byu.edu)
* @see EventListener
* @since 1.1
* @status updated to 1.4
*/
public class EventObject implements Serializable
{
/**
* Compatible with JDK 1.1+.
*/
private static final long serialVersionUID = 5516075349620653480L;
/**
* The source object; in other words, the object which this event takes
* place on.
*/
protected transient Object source;
/**
* Constructs an EventObject with the specified source.
*
* @param source the source of the event
* @throws IllegalArgumentException if source is null (This is not
* specified, but matches the behavior of the JDK)
*/
public EventObject(Object source)
{
// This check for null is stupid, if you ask me, since source is
// protected and non-final, so a subclass can set it to null later on.
if (source == null)
throw new IllegalArgumentException();
this.source = source;
}
/**
* Returns the source of the event.
*
* @return the event source
*/
public Object getSource()
{
return source;
}
/**
* Converts the event to a String. The format is not specified, but by
* observation, the JDK uses:
* <code>getClass().getName() + "[source=" + source + "]";</code>.
*
* @return String representation of the Event
*/
public String toString()
{
return getClass().getName() + "[source=" + source + "]";
}
} // class EventObject