Programming and Problem Solving with Java

423

outPane = out.getContentPane();

out.setSize( 300 , 200 );

out.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

outPane.setLayout(new GridLayout( 0 , 1 ));

price = 30 ;

cost = price * LBS;

ch = 'A';

outPane.add(newJLabel("Cost is "));

outPane.add(newJLabel(""+ cost));

outPane.add(newJLabel("Price is " + price + "Cost is "+ cost));

outPane.add(newJLabel("Grade "+ ch + " costs "));

outPane.add(newJLabel(""+ cost));

out.setVisible(true);

}

}

3.To use each of the following statements, a Java application must importwhich
package(s)?
a.outPane.add(new JLabel("x"));
b.private static classButtonHandler implementsActionListener
c. outPane.setLayout(new GridLayout( 0 , 2 ));

4.Given the statements

String heading;

String str;

heading = "Exam Preparation Exercises";

what is the output of each of the following code segments?

a.outPane.add(newJLabel(""+ heading.length()));

b.outPane.add(newJLabel(heading.substring( 6 , 16 )));

c. outPane.add(newJLabel(""+ heading.indexOf("Ex")));

5.Name three kinds of objects that can be contained in the content pane of a
JFrameobject.

6.What are the steps in adding a data entry field to the content pane of a JFrame
object in Java?

7.What determines the amount of information in a prompt?

8.(True or False?) A JPanelcan hold just one user interface element.