利用接口做参数,写个计算器,能完成加减乘除运算。
(1)定义一个接口Compute含有一个方法int computer(int n, int m);
(2)设计四个类分别实现此接口,完成加减乘除运算;
(3)设计一个类UseCompute,类中含有方法:public void useCom(Compute com, int one, int two),此方法能够用传递过来的对象调用computer方法完成运算,并输出运算的结果;
(4)设计一个主类Test,调用UseCompute中的方法useCom来完成加减乘除
运算。
接口
package nchu.demo;
public interface Compute {
public abstract int computer(int n,int m);
}
加减乘除
package nchu.demo;
public class Add implements Compute{
public Add() {
}
@Override
public int computer(int n, int m) {
return m+n;
}
}
package nchu.demo;
public class Subtract implements Compute{
public Subtract() {
}
@Override
public int computer(int n, int m) {
return n-m;
}
}
package nchu.demo;
public class Multiply implements Compute{
public Multiply() {
}
@Override
public int computer(int n, int m) {
return m*n;
}
}
package nchu.demo;
public class Except implements Compute{
public Except() {
}
@Override
public int computer(int n, int m) {
return n/m;
}
}
使用计算器
package nchu.demo;
public class UseCompute {
public UseCompute() {
}
public void useCom(Compute com, int one, int two){
double i = com.computer(one,two);
System.out.println("计算结果为:" + i);
}
}
Test
package nchu.demo;
public class Test {
public static void main(String[] args) {
Compute a=new Add();
Compute b=new Subtract();
Compute c=new Multiply();
Compute d=new Except();
UseCompute Use = new UseCompute();
//加减乘除
Use.useCom(a,1,2);
Use.useCom(b,1,2);
Use.useCom(c,1,2);
Use.useCom(d,1,2);
}
}