Question

help on Pick a pair of concrete classes in the JDK in a parent-child relationship and discuss a few polymorphic and/or overloaded methods. Do not use Object as the parent class - it is too trivial to address the issues to be addressed here, and in any case, Object is the final parent of all classes in Java???

Answer 1

1)You can take example of JButton class javax.swing.JButton.java

Ref : http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/6-b14/javax/swing/JButton.java

2) AbstractButton.java is parent clss for JButton(javax/swing/AbstractButton.java)

3) In JButton class there are 2 overloaded functions

(Funtion with same name and different parameters)   

These are 2 constructors (Initilization of class)

//JButton Constructor with Button Text and Button Background Icon  
public 1x1.gifJButton(String text, Icon icon) {
}   

//JButton Constructor with on Button (Default Background will be used)  
public 1x1.gifJButton(String text) {
}

4)The above I explained is Compile time polymorphism (Same Method names)

5)And also RunTimeException.java and ArithmaticException.java are in Inheritence relationship