java简单工厂设计模式实现计算器

分手后的思念是犯贱 2022-06-07 12:11 203阅读 0赞

本文使用java的简单工厂设计模式实现简单计算器。

一、项目工程如下：

![Center][]

二、Operation类是计算器的父类：

package 计算器;
    /**
     * 计算器的父类
     * @author Administrator
     *
     */
    public abstract class Operation {
    	private double x;
    	private double y;
    	public abstract double getResult();
    	public double getX() {
    		return x;
    	}
    	public void setX(double x) {
    		this.x = x;
    	}
    	public double getY() {
    		return y;
    	}
    	public void setY(double y) {
    		this.y = y;
    	}
    }

三、Add类：

package 计算器;
    /**
     * 加
     * @author Administrator
     *
     */
    public class Add extends Operation{
    	@Override
    	public double getResult() {
    		return getX()+getY();
    	}
    }

四、Sub:

package 计算器;
    /**
     * 减
     * @author Administrator
     *
     */
    public class Sub extends Operation{
    	@Override
    	public double getResult() {
    		return getX()-getY();
    	}
    }

五、Mul

package 计算器;
    /**
     * 乘
     * @author Administrator
     *
     */
    public class Mul extends Operation{
    	@Override
    	public double getResult() {
    		return getX()*getY();
    	}
    }

六、Div

package 计算器;
    /**
     * 除
     * @author Administrator
     *
     */
    public class Div extends Operation{
    	@Override
    	public double getResult() {
    		if (getY()==0) {
    			System.out.println("除数不能为0");
    			return -1;
    		}else{
    			return getX()/getY();
    		}
    	}
    }

七、工厂类：

package 计算器;
    
    public class OptionerFactory {
    	public static Operation creatOperation(String oper){
    		Operation operation=null;
    		switch (oper) {
    		case "+":
    			operation=new Add();
    			break;
    		case "-":
    			operation=new Sub();
    			break;
    		case "*":
    			operation=new Mul();
    			break;
    		case "/":
    			operation=new Div();
    			break;
    		}
    		return operation;
    	}
    }

八、测试类：

package 计算器;
    
    import java.util.Scanner;
    
    public class TestMain {
    	public static void main(String[] args) {
    		@SuppressWarnings("resource")
    		Scanner scanner=new Scanner(System.in);
    		System.out.println("输入第一个数");
    		double x=scanner.nextInt();
    		System.out.println("输入操作符");
    		String oper=scanner.next();
    		System.out.println("输入第二个数");
    		double y=scanner.nextInt();
    		Operation operation = OptionerFactory.creatOperation(oper);
    		operation.setX(x);
    		operation.setY(y);
    		double result = operation.getResult();
    		System.out.println("结果："+result);
    	}
    }

九、架构图：

![SouthEast][]

[Center]: /images/20220607/109520c5afac463e98e909901bc74f66.png
[SouthEast]: /images/20220607/730e8c370d46432287b8730e34a65776.png