how to implement Observer

[sk8ergirl]

Hi,
I'm working on my assignment there are two parts of the assignment first part was to create class (ClassOne,ClassTwo,ClassThree,ClassFour,ClassFive)
ClassFive extends ClassTwo and ClassTwo is abstract

the secod part is to add the iobserver and iSubject , but I don't know how to implemet this part
in the UML diagram it show that
ClassOne is connected to iObserver and iSubject
ClassThree is connected to iObserver
ClassFour is connected to iObserver and iSubject
ClassFive is connected to iObserver and iSubject
the arrows are dotted

can you explain to me which class extend and implements iObserve and iSubject and how can I determine which class extend or implments which class

thank you in advance

[JamesCherrill]

In Java a class can diectly extend one superclass, and implement any number of interfaces.

Java's "extend a superclass" is called "generalisation" in UML. The UML representation of a Generalization is a hollow triangle shape on the superclass end of a solid line or lines that connect it to one or more subclasses.

Java's "implementing an interface" is called "realisation" in UML. The UML representation of a Realization is a hollow triangle shape on the interface end of a dashed line or lines that connect it to one or more implementers.

[sk8ergirl]

called

Java's "extend a superclass" is called "generalisation" in UML. The UML representation of a Generalization is a hollow triangle shape on the superclass end of a solid line or lines that connect it to one or more subclasses.

Thank you I think I figured it out