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 How do you specify what the program should do when the user clicks a button?

You have a class that extends the JComponent class. In this class you have created a painted graphical object. Your code will change the data in the graphical object. What additional code is needed to ensure that the graphical object will be updated with the changed data?  

Consider the classes shown below: public class Parent { public int getValue() { return 24; } public void display() { System.out.print(getValue() + ” “); } } public class Child extends Parent { public int getValue() { return -7; } } Using the classes above, what is the output of the following lines of code? Child kid = new Child(); Parent adult = new Parent(); kid.display(); adult.display();

When method makeMenuItem is called, how many objects are being created? public JMenuItem makeMenuItem(final String menuLabel) { JMenuItem mi = new JMenuItem(menuLabel); class MyMenuListener implements ActionListener { public void actionPerformed(ActionEvent e) { doSomethingElse(); System.out.println(menuLabel); } } mi.addActionListener(new MyMenuListener()); return mi; }

After 9 iterations of selection sort working on an array of 10 elements, what must hold true?

Complete the following code snippet, which is intended to be a recursive method that will find the smallest value in an array of double values from index to the end of the array: public static double minVal(double[] elements, int index) { if (index == elements.length – 1) { __________________ } double val = minVal(elements, index + 1); if (elements[index] < val) { return elements[index]; } else { return val; } }

You have a class that extends the JComponent class. In this class you have created a painted graphical object. Your code will change the data in the graphical object. What additional code is needed to ensure that the graphical object will be updated with the changed data?  

Which statement is true about a subclass that uses the same method name but different parameter types for a method that appears in its superclass?

Complete the following code snippet, which is intended to be a recursive method that will find the smallest value in an array of double values from index to the end of the array: public static double minVal(double[] elements, int index) { if (index == elements.length – 1) { __________________ } double val = minVal(elements, index + 1); if (elements[index] < val) { return elements[index]; } else { return val; } }

Which statement is true about a subclass that uses the same method name but different parameter types for a method that appears in its superclass?