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class MyAssociation extends Association {
...
}
synchronized public Object valueForKey(String key) {
Object dest = this.destination();
if (key.equals("title")) {
return ((MyApplet)dest).getLabel();
}
}
synchronized public void takeValueForKey(Object value, String key) {
Object dest = this.destination();
if (key.equals("title")) {
if ((value != null) && !(value instanceof String)) {
System.out.println("Object value of wrong type set for key
'title'. Value must be a String.");
} else {
((MyApplet)dest).setLabel(((value == null)
? ""
: (String)value));
}
}
Note that the class of the destination applet (in this example, MyApplet) must be cast.
// fictictious method
public void observeGadget(Object sender, String action) {if ((sender instanceof Gadget) && action.equals("vacuum")) {
this.invokeAction(action);
}
}
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