menutest.java

Java程序设计技巧与开发实例附书源代码。

public class MenuTest
    implements MenuUser
{
   private final String[] MAIN_MENU =
       {
       "[A] compute 10*20",
       "[T] for trig menu ..."};
   private final String[] SUB_MENU =
       {
       "[1] to compute sin(2)",
       "[2] to compute cos(2)"};
   private Menu mainMenu = null;
   private Menu subMenu = null;

   public MenuTest()
   {
      mainMenu = new Menu("Multiplication", MAIN_MENU, this);
   }

   public void performAction(String command)
   {
      if (command.equalsIgnoreCase("A"))
      {
         System.out.println("Result: " + (10 * 20));
      }
      else if (command.equalsIgnoreCase("T"))
      {
         subMenu = new Menu("Trigonometry", SUB_MENU, this);
      }
      else if (command.equalsIgnoreCase("1"))
      {
         System.out.println("sin(2) = " + Math.sin(2.0));
      }
      else if (command.equalsIgnoreCase("2"))
      {
         System.out.println("cos(2) = " + Math.cos(2.0));
      }
   }

   public static void main(String args[])
   {
      MenuTest mt = new MenuTest();
   }
}