Digital Music Programming Mid-term Exam (Fujinaga, March 1998)
1. Answer the following questions (5 points each):
2. Create a class Rectangle. Use float variables to represent length and width, both of which defaults to 1 (15 points).
It should at least have:
3. Find errors in the Java source code below. There are at least ten errors (10 points):
import java.awt.*; import java.awt.event.*; public class Index extends Applet implements ActionListener { private TextArea input, output; private Button b; private int count; public void init() { b = new Button( "Click here to enter text" ); b.addActionListener( this ); prompt = new Label( Enter some text: ); input = new TextArea( 20, 20 ); add( prompt ); add( input ); add( output ); }
public void paint( ActionEvent g ) { count = 0; output.setText(""); String alphabet[26] = "abcdefghijklmnopqrstuvwxyz"; String s = input.getText().toLowerCase(); for (i = 0; i < alphabet.length(); i++ ); g.drawString(alphabet[i], 10, 10); system.out.println(s);
}