这个小demo,不知道有没面向对象的思想在里面？

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这个小demo,不知道有没面向对象的思想在里面？5

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import com.shenchen.model.Item;
import com.shenchen.type.Types;
import com.shenchen.util.Calculator;

public class Main {

	public static void main(String[] args) throws Exception, IOException {

		InputStreamReader isr = new InputStreamReader(System.in);
		BufferedReader br = new BufferedReader(isr);
		Item item = new Item();
		Double num1 = Double.parseDouble( br.readLine());
		item.setNum1(num1);

		System.out.println("请输入一个运算符号：");
		String str = br.readLine();
		switch (str) {
		case "+":
			item.setType(Types.JIA);
			break;

		case "-":
			item.setType(Types.JIAN);
			break;

		case "*":
			item.setType(Types.CHENG);
			break;

		case "/":
			item.setType(Types.CHU);
			break;
		default:
			System.out.println("符号错误！");
			System.exit(0);
		}

		System.out.println("请输入一个数字：");
		Double num2 = Double.parseDouble(br.readLine());
		item.setNum2(num2);

		new Calculator(item);
	}
}

public class Item {
	double num1;
	double num2;
	int type;

	public void setNum1(double num1) {
		this.num1 = num1;
	}

	public void setNum2(double num2) {
		this.num2 = num2;
	}

	public void setType(int type) {
		this.type = type;
	}

	public double getNum1() {
		return num1;
	}

	public double getNum2() {
		return num2;
	}

	public int getType() {
		return type;
	}

}

public class Types {
	public final static int JIA = 1;
	public final static int JIAN = 2;
	public final static int CHENG =3;
	public final static int CHU = 4;
	
}


import com.shenchen.model.Item;
import com.shenchen.type.Types;

public class Calculator {
	double result;
	public Calculator(Item item) {
		double num1 = item.getNum1();
		double num2 = item.getNum2();
		switch (item.getType()) {
		case Types.JIA:
			result = num1+num2;
			System.out.println(num1+"+"+num2+" = "+result);
			break;
		case Types.JIAN:
			result = num1-num2;
			System.out.println(num1+"-"+num2+" = "+result);
			break;
		case Types.CHENG:
			result = num1*num2;
			System.out.println(num1+"*"+num2+" = "+result);
			break;
		case Types.CHU:
			result = num1/num2;
			System.out.println(num1+"/"+num2+" = "+result);
			break;		
		}
		
	}
}

问题补充：如果不是，能不能指点一下。大概得怎么写。最好是贴出代码啦，学习学习

面向对象 java

2014年6月20日 23:46

于阳生
26
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2个答案按时间排序按投票排序

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采纳的答案

将计算的抽一个接口出来ICalculator，具体计算实现该接口。如果要加功能，添加其它计算方法，添加实现类就好了，另外可以弄一个Factory负责创建这些Calculator。代码简单贴一下。

public interface ICalculator {
	public double calculate(double ...args);
}

//加法
public class PlusCalculator implements ICalculator {
	@Override
	public double calculate(double... args) {
		double res = 0;
		for(double arg:args)
			res += arg;
		return res;
	}
}

//减法
public class MinusCalculator implements ICalculator {

	@Override
	public double calculate(double... args) {
		if (args.length == 0)
			return 0;
		double res = args[0];
		for (int i = 1; i < args.length; ++i) {
			res -= args[i];
		}
		return res;
	}
}

//平方
public class SquareCalculator implements ICalculator {
	@Override
	public double calculate(double... args) {
                //只接受一个参数
		if(args.length == 1)
			return args[0]*args[0];
		else
			return 0;
	}
}

//操作类型
public enum CalculatorType {
PlusCalculator,MinusCalculator,SquareCalculator;
}

//工厂
public class CalculatorFactory {

	public static ICalculator getCalculator(CalculatorType type) {
		ICalculator calculator = null;
		switch (type) {
		case MinusCalculator:
			calculator = new MinusCalculator();
			break;
		case PlusCalculator:
			calculator = new PlusCalculator();
			break;
		case SquareCalculator:
			calculator = new SquareCalculator();
			break;
		default:
			break;
		}
		return calculator;
	}
}

//测试代码
	public static void main(String[] args) {
		double arg1 = 100;
		double arg2 = 90;
		double arg3 = 80;
		ICalculator calculator = CalculatorFactory.getCalculator(CalculatorType.PlusCalculator);
		System.out.println(calculator.calculate(arg1,arg2,arg3));
		calculator = CalculatorFactory.getCalculator(CalculatorType.MinusCalculator);
		System.out.println(calculator.calculate(arg1,arg2,arg3));
		calculator = CalculatorFactory.getCalculator(CalculatorType.SquareCalculator);
		System.out.println(calculator.calculate(arg1));
		
	}

2014年6月21日 23:21