2.15


// An addition program 

import javax.swing.JOptionPane;  // import class JOptionPane

public class Addition {
   public static void main( String args[] )
   {
      String firstNumber,   // first string entered by user
             secondNumber;  // second string entered by user
      int number1,          // first number to add
          number2,          // second number to add
          sum;              // sum of number1 and number2

      // read in first number from user as a string
      firstNumber =
         JOptionPane.showInputDialog( "Enter first integer" );

      // read in second number from user as a string
      secondNumber =
         JOptionPane.showInputDialog( "Enter second integer" );

      // convert numbers from type String to type int
      number1 = Integer.parseInt( firstNumber ); 
      number2 = Integer.parseInt( secondNumber );

      // add the numbers
      sum = number1 + number2;

      // display the results
      JOptionPane.showMessageDialog(
         null, "The sum is " + sum, "Results",
         JOptionPane.PLAIN_MESSAGE );

      System.exit( 0 );   // terminate the program
   }
}

这个程序弹出对话框获取用户输入的两个整数,然后将其相加并显示结果。程序首先导入了JOptionPane类,该类提供了弹出对话框的功能,用于与用户进行交互。然后,在main方法中,定义了几个变量:firstNumber和secondNumber用于存储用户输入的两个整数(以字符串形式),number1和number2用于存储将字符串转换为整数后的结果,sum用于存储两个整数的和。接下来,使用JOptionPane.showInputDialog方法弹出对话框,提示用户输入第一个整数和第二个整数,并将用户输入的结果存储到firstNumber和secondNumber中。然后,使用Integer.parseInt方法将firstNumber和secondNumber转换为整数类型,并将结果存储到number1和number2中。接着,将number1和number2相加,将结果存储到sum中。最后,使用JOptionPane.showMessageDialog方法弹出对话框,显示计算结果sum。

posted @ 2024-02-15 20:40  cor0000  阅读(13)  评论(0)    收藏  举报