xuxiaolei wrote:
import javax.swing.JOptionPane;
public class killua
{
  public static void main( String args[] )
  {
    String firstNumber, secondNumber, thirdNumber;
    int number1, number2, number3, result; // 用来记录最后结果的变量

    firstNumber = JOptionPane.showInputDialog( "请输入第一个数:" );
    secondNumber = JOptionPane.showInputDialog( "请输入第二个数:" );
    thirdNumber = JOptionPane.showInputDialog( "请输入第三个数:" );

    number1 = Integer.parseInt(firstNumber);
    number2 = Integer.parseInt(secondNumber);
    number3 = Integer.parseInt(thirdNumber);

    result = number1 * number2 * number3; //这里提示找不到符号
    JOptionPane.showMessageDialog(null, "三个数的乘积是: " + result);
    
    //这句没有必要
    //System.exit( 0 );
  }
}