Java How to Program Fourth Edition - DCC

360 Arrays Chapter 7
Fig. Fig. 7.26 7.26 The 36 possible outcomes of rolling two dice.
roll the dice 36,000 times. Use a single-subscripted array to tally the numbers of times each possible
sum appears. Display the results in a JTextArea in tabular format. Also, determine whether the totals
are reasonable (i.e., there are six ways to roll a 7, so approximately one sixth of all the rolls should
be 7). The applet should use the GUI techniques introduced in Chapter 6. Provide a JButton to allow
the user of the applet to roll the dice another 36,000 times. The applet should reset the elements
of the single-subscripted array to 0 before rolling the dice again.
7.16 What does the program of Fig. 7.27 do?
1 // Exercise 7.16: WhatDoesThisDo.java
2
3 // Java core packages
4 import java.awt.*;
5
6 // Java extension packages
7 import javax.swing.*;
8
9 public class WhatDoesThisDo extends JApplet {
10 int result;
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12 public void init()
13 {
14 int array[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
15
16 result = whatIsThis( array, array.length );
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18 Container container = getContentPane();
19 JTextArea output = new JTextArea();
20 output.setText( "Result is: " + result );
21 container.add( output );
22 }
23
24 public int whatIsThis( int array2[], int size )
25 {
26 if ( size == 1 )
27 return array2[ 0 ];
Fig. Fig. 7.27 7.27 Determine what this program does.
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© Copyright 1992–2002 by Deitel & Associates, Inc. All Rights Reserved. 7/3/01
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