Java语法基础课后作业

                            import javax.swing.JOptionPane;  // import class JOptionPanepublicclass Test5 {
   publicstaticvoid main( String args[] )
   {
      String firstNumber,   // first string entered by user
             secondNumber;  // second string entered by userint number1,          // first number to add
          number2,          // second number to add
          sum,              // sum of number1 and number2
          subtraction,      // subtraction of number1 and number2
          product,          // product of number1 and number2
          division = 0;         // division of number1 and number2

      // read in first number from user as a string
      firstNumber =
         JOptionPane.showInputDialog( "输入第一个数" );

      // read in second number from user as a string
      secondNumber =
         JOptionPane.showInputDialog( "输入第二个数" );

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

      // add the numbers
      sum = number1 + number2;
      
      //multiply the numbers
      product = number1 * number2;
      
      //divide the numbersif( number2 == 0 )
          JOptionPane.showMessageDialog(
                     null, "分母为零,无法计算两数相除", "Results",
                     JOptionPane.PLAIN_MESSAGE );
      else
          division = number1 / number2;
      
      //minus the numbers
      subtraction = number1 - number2;
      

      // display the results      JOptionPane.showMessageDialog(
         null, "The sum is " + sum 
         + " \nThe subtraction is " + subtraction 
         + " \nThe product is " + product
         + " \nThe division is " + division, "Results",
         JOptionPane.PLAIN_MESSAGE );

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

                            import
                             javax.swing.JOptionPane;


                            public
                            class
                             Test6 {
    
    
                            public
                            static
                            void
                             main(String[] args) 
    {
        
                            //
                            定义一个空字符串
        String result = "";
        String Input = "";
        
        //进行6次循环for(int i = 0 ; i < 6 ; i ++)
        {
            //生成一个97～122的int型的整数int intVal = (int)(Math.random() * 26 + 97);
            //将intValue强制转换为char后连接到result后面
            result = result + (char)intVal;
        }
       
//输出验证码
        JOptionPane.showMessageDialog(
                 null, "验证码：" + result, "Results",
                 JOptionPane.PLAIN_MESSAGE );
//用户输入验证码
        Input =
                 JOptionPane.showInputDialog( "输入验证码" );
//判断是否一致
        if(Input.equals(result))
            JOptionPane.showMessageDialog(
                     null, "验证码输入正确", "Results",
                     JOptionPane.PLAIN_MESSAGE );
        else
            JOptionPane.showMessageDialog(
                     null, "Error", "Results",
                     JOptionPane.PLAIN_MESSAGE );
        
     }

}