两数相加（输入框）

目标：在两个输入框分别输入两个整数，弹出两数相加的结果
代码：
 1 package com.test;
 2 
 3 //An addition program 
 4 
 5 import javax.swing.JOptionPane;  // import class JOptionPane
 6 
 7 public class Adition {
 8 public static void main( String args[] )
 9 {
10    String firstNumber,   // first string entered by user
11           secondNumber;  // second string entered by user
12    int number1,          // first number to add
13        number2,          // second number to add
14        sum;              // sum of number1 and number2
15 
16    // read in first number from user as a string
17    firstNumber =
18       JOptionPane.showInputDialog( "Enter first integer" );
19 
20    // read in second number from user as a string
21    secondNumber =
22       JOptionPane.showInputDialog( "Enter second integer" );
23 
24    // convert numbers from type String to type int
25    number1 = Integer.parseInt( firstNumber ); 
26    number2 = Integer.parseInt( secondNumber );
27 
28    // add the numbers
29    sum = number1 + number2;
30 
31    // display the results
32    JOptionPane.showMessageDialog(
33       null, "The sum is " + sum, "Results",
34       JOptionPane.PLAIN_MESSAGE );
35 
36    System.exit( 0 );   // terminate the program
37 }
38 }
测试截图：