多态的设计应用及实现之汽车租价计算

目标: 多态的设计应用及实现.

汽车出租商准备根据汽车购买的价格及汽车种类来制定
各种汽车的每日租金.
具体规则如下:

家用轿车: 购买价格 * (1/1000) + 10
旅行车: 购买价格 * (2/1000)
越野车: 购买价格 * (3/1000)
大客车: 购买价格 * (3/1000) + 400

计算并生成价格清单, 并在大客车前面加上'*'来标识. 输出结果按购买日期降序排列.
源文件及输出文件的价格单位都精确到元. 计算中出现不足1元的部分以1元来计算.
汽车分类及计算方法可能会根据今后业务发展情况调整, 因此请尽量保持代码易于修改和维护.

源文件格式:（源文件请自行编制，文件名请用src.txt）
车辆名称 购买价格 购买日期 车辆类型
金杯 100000 2007-08-02 旅行车
宝马X5 1000000 2007-01-29 越野车
别克 80201 2008-02-06 家用轿车
黄海 1200000 2009-01-03 大客车

输出格式: [标记] [购买价格] [购买日期] [车辆类型] [计算后价格]（输出文件文件名请用dst.txt）
* 黄海 1200000 2009-01-03 大客车 4000

package com.neusoft;
import java.util.*;
import java.io.*;
import java.math.BigDecimal;
import java.text.*;


/**
 * 主函数类
 * @author 
 *
 */
public class MainRent {
	
	public static List<Car> readFile() throws IOException{
		List<Car> carList = new ArrayList<Car>();
		String s = "";
		BufferedReader br=null;
		try{
			br = new BufferedReader(new FileReader("c:\\src.txt"));
			try{
				
				while(((s=br.readLine())!=null)){	
					
					Car car;					
					String[] buf = s.split(" ");					
					if(buf[3].equals("大客车"))
						car= new BigBus();
					else if(buf[3].equals("旅行车"))
						car = new TravelCar();
					else if(buf[3].equals("越野车"))
						car= new YueyeCar();
					else
						car = new HomeCar();
					
					car.setCarName(buf[0]);
					car.setPrice(new BigDecimal(buf[1]));
					SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
					Date date = sdf.parse(buf[2]);
					car.setDate(date);
					car.setCarClass(buf[3]);
					carList.add(car);
						
					
					
				}
			}catch(Exception e){
				e.printStackTrace();
			}
		}catch(FileNotFoundException e){
			e.printStackTrace();
		}finally{
			if(br!=null){				
				br.close();
				System.out.println("文件关闭");
			}
		}
		
		return carList;
	}
	
	
	public static void writeFile(List<Car> carList){
		BufferedWriter bw=null;
		try{
			 bw= new BufferedWriter(new FileWriter("c:/dst.txt"));
			for(Iterator<Car> it = carList.iterator();it.hasNext();){
				bw.write(it.next().toString());
				bw.newLine();
			}
			bw.close();
			
			
		}catch(Exception e){
			e.printStackTrace();
		}finally{
			try {
				bw.close();
				System.out.println("再次关闭文件");
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		
	}
	
	
	public static void main(String[] args) throws IOException{
		List<Car>carList = readFile();
		Collections.sort(carList, new Comparator<Object>(){
			public int compare(Object o1,Object o2){
				Car car1 = (Car)o1;
				Car car2 = (Car)o2;
				return car2.getDate().compareTo(car1.getDate());
			}
		});	
		writeFile(carList);
		
	}

}




package com.neusoft;

import java.math.BigDecimal;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * 洗车的基础类
 * 
 * @author 
 * 
 */
public class Car {

	protected String carName;// 车辆名称
	protected BigDecimal price;// 购买价格
	protected Date date;// 购买日期
	protected String carClass;// 车辆类别

	/**
	 * 计算租金
	 * 
	 * @return BigDecimal 
	 */

	public BigDecimal countRent1() {
		return new BigDecimal("0");
	}

	/**
	 * @return the carClass
	 */
	public String getCarClass() {
		return carClass;
	}

	/**
	 * @return the carName
	 */
	public String getCarName() {
		return carName;
	}

	/**
	 * @return the date
	 */
	public Date getDate() {
		return date;
	}

	/**
	 * @return the price
	 */
	public BigDecimal getPrice() {
		return price;
	}

	/**
	 * @param carClass
	 *            the carClass to set
	 */
	public void setCarClass(String carClass) {
		this.carClass = carClass;
	}

	/**
	 * @param carName
	 *            the carName to set
	 */
	public void setCarName(String carName) {
		this.carName = carName;
	}

	/**
	 * @param date
	 *            the date to set
	 */
	public void setDate(Date date) {
		this.date = date;
	}

	/**
	 * @param price
	 *            the price to set
	 */
	public void setPrice(BigDecimal price) {
		this.price = price;
	}

	public String toString() {
		String ret = "";
		if (carClass.equals("大客车"))
			ret += "*";
		else
			ret += " ";
		ret += carName + " " + price + " "
				+ new SimpleDateFormat("yyyy-MM-dd").format(date) + " "
				+ carClass + " " + countRent1();
		return ret;
	}

}





package com.neusoft;

import java.math.BigDecimal;

/**
 * 大客车类，继承基础车类
 * 
 * @author 
 * 
 */
public class BigBus extends Car {

	@Override
	public BigDecimal countRent1() {
		BigDecimal ret = null;

		ret = price
				.multiply(new BigDecimal("3").divide(new BigDecimal("1000")))
				.add(new BigDecimal("400"));
		ret = ret.setScale(0, BigDecimal.ROUND_CEILING);
		return ret;
	}

}



package com.neusoft;

import java.math.BigDecimal;

/**
 * 家用轿车类，继承基础车类
 * 
 * @author 
 * 
 */
public class HomeCar extends Car {

	@Override
	public BigDecimal countRent1() {
		BigDecimal ret = null;
		ret = price
				.multiply(new BigDecimal("1").divide(new BigDecimal("1000")))
				.add(new BigDecimal("10"));
		ret = ret.setScale(0, BigDecimal.ROUND_CEILING);
		return ret;
	}

}




package com.neusoft;

import java.math.BigDecimal;

/**
 * 旅行车类，继承基础车类
 * 
 * @author 
 * 
 */
public class TravelCar extends Car {

	@Override
	public BigDecimal countRent1() {
		BigDecimal ret = null;
		ret = price
				.multiply(new BigDecimal("2").divide(new BigDecimal("1000")));
		ret = ret.setScale(0, BigDecimal.ROUND_CEILING);
		return ret;
	}

}







package com.neusoft;

import java.math.BigDecimal;

/**
 * 越野车类，继承基础车类
 * 
 * @author 
 * 
 */
public class YueyeCar extends Car {

	@Override
	public BigDecimal countRent1() {
		BigDecimal ret = null;
		ret = price
				.multiply(new BigDecimal("3").divide(new BigDecimal("1000")));
		ret = ret.setScale(0, BigDecimal.ROUND_CEILING);
		return ret;
	}

}