你那样写可以啊，就你注释掉的那些调用方法，也可以用多态public class Pan { public static void main(String[] args) {String cc = "/";Operation o = null;if (cc.equals("+")) { o = new Jia();
}else if (cc.equals("-")){ o = new Jian();
}else if (cc.equals("*")){ o = new Chen();
}else if (cc.equals("/")){ o = new Chu();
}System.o...
类似的:class Jia{public int computer(int a, int b){return a + b;}}class Jian{public int computer(int a, int b){return a - b;}}class Cheng{public int computer(int a, int b){...
