面向对象第七章课后作业

第七章综合练习：

package com.project.demo;

import java.util.Scanner;

import org.apache.log4j.Logger;

/**
 * 动物父类
 * @author suixin
 *
 */
public abstract class Animal {
	
	private static Logger logger = Logger.getLogger(Animal.class.getName());
	
	private String name  = ""; //昵称
	

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	
	public Animal() {
		super();
		// TODO Auto-generated constructor stub
	}

	public Animal(String name) {
		super();
		this.name = name;
	}
	
	public abstract void shout() ; //动物叫
	
}


package com.project.demo;

/**
 * 猫类
 * @author suixin
 *
 */
public class Cat extends Animal implements Terrestrial{

	private int letNum = 0; //腿数量
	
	@Override
	public void shout() {
		// TODO Auto-generated method stub
		System.out.println("喵喵喵......");
	}

	public Cat() {
		super();
		// TODO Auto-generated constructor stub
	}

	public Cat(String name,int letNum ) {
		super(name);
		this.letNum = letNum;
		// TODO Auto-generated constructor stub
	}

	@Override
	public int getLegNum() {
		// TODO Auto-generated method stub
		return letNum;
	}
	
	
}


package com.project.demo;

/**
 * 海豚类
 * @author suixin
 *
 */
public class Dolphin extends Animal {

	public Dolphin() {
		super();
		// TODO Auto-generated constructor stub
	}

	public Dolphin(String name) {
		super(name);
		// TODO Auto-generated constructor stub
	}

	@Override
	public void shout() {
		// TODO Auto-generated method stub
		System.out.println("海豚音......");
	}
	
}


package com.project.demo;

/**
 * 鸭类
 * @author suixin
 *
 */
public class Duck extends Animal implements Terrestrial{

	private int letNum = 0; //腿数量
	
	public Duck() {
		super();
		// TODO Auto-generated constructor stub
	}

	public Duck(String name,int letNum) {
		super(name);
		this.letNum = letNum;
		// TODO Auto-generated constructor stub
	}

	@Override
	public void shout() {
		// TODO Auto-generated method stub
		System.out.println("嘎嘎嘎......");
	}

	@Override
	public int getLegNum() {
		// TODO Auto-generated method stub
		return letNum;
	}
	
}


package com.project.demo;

/**
 * 获取腿的数量的接口
 * @author suixin
 *
 */
public interface Terrestrial {
	 
	int getLegNum(); //腿的数量
}


package com.project.demo;

import java.util.Scanner;

/**
 * 测试类
 * @author suixin
 *
 */
public class Test {
	//创建动物类对象数组
	static Animal animal []  = new Animal[3];
	static Scanner scanner = new Scanner(System.in);
	static int choose;
	
	public static void main(String[] args) {
		 start();
		 while (choose != 0) {
			try {
				modifyAnimal();
			} catch (Exception e) {
				// TODO: handle exception
				e.printStackTrace();
			} finally {
				show();
				choose = scanner.nextInt();
			}
		}
	}
	
	/**
	 * 打印信息方法
	 */
	public static void show() {
		System.out.println("动物名字\t\t腿的条数\t\t动物叫");
		for (int i = 0; i < animal.length; i++) {
			if (animal[i] != null) {
				if (animal[i] instanceof Terrestrial) {
					String name = animal[i].getName();
					int legNum = ((Terrestrial) animal[i]).getLegNum();
					System.out.print(name + "\t\t" + legNum + "\t\t");
					animal[i].shout();
				}else {
					String name = animal[i].getName();
					System.out.print(name + "\t\t" + 0 + "\t\t");
					animal[i].shout();
				}
			}

		}
		System.out.println("是否要继续修改数据：按0进行修改操作，其它任意数字键退出:");
	}
	
	/**
	 * 给对象数组初始化
	 */
	public static void start() {
		animal[0] = new Cat("加菲猫", 4);
		animal[1] = new Duck("唐小鸭", 2);
		animal[2] = new Dolphin("海豚奇奇");
		show();
		choose = scanner.nextInt();
	}
	
	/**
	 * 更改信息方法
	 * @throws Exception
	 */
	public static void modifyAnimal() throws Exception{
		//定义变量存储临时数据
		String [] names = new String[3];
		
		int [] number = new int [3];
		System.out.print("请输入猫的名称：");
		names[0] = scanner.next();
		System.out.println("请输入猫腿的条数");
		number[0] = scanner.nextInt();
		if (number[0] != 4) {
			throw new Exception("猫只能有4条腿");
		}
		System.out.println("请输入鸭子的名称");
		names[1] = scanner.next();
		System.out.println("请输入鸭子腿的条数");
		number[1] = scanner.nextInt();
		if (number[1] != 2) {
			throw new Exception("鸭子只能有两条腿");
		}
		System.out.println("请输入海豚的名称");
		names[2] = scanner.next();
		animal[0] = new Cat(names[0], number[0]);
		animal[1] = new Duck(names[1], number[1]);
		animal[2] = new Dolphin(names[2]);
	}
}

（1）编写能产生ArrayIndexOutOfBoundsException异常的代码，并将其捕获，在控制台上输出异常信息。

package com.homework.demo.test7;

public class ArraysIndex {
	
	public static void main(String[] args) {
		int arr [] = new int [3];  //长度为3的整型数组
		try {
			arr[3] = 2; //下标为3的元素赋值为2（数组越界）
		} catch (ArrayIndexOutOfBoundsException e) {  //数组下标越界
			// TODO: handle exception
			e.printStackTrace();
		}
	}
}

（2）修改第一题，使用log4j记录日志，在jbit.log文件中记录产生的异常信息。

package com.homework.demo.test7;

import org.apache.log4j.Logger;

public class ArraysIndexLog {
	
	private static Logger logger = Logger.getLogger(ArraysIndexLog.class.getName());
	
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int arr [] = new int [3];  //长度为3的整型数组
		try {
			arr[3] = 2; //下标为3的元素赋值为2（数组越界）
		} catch (ArrayIndexOutOfBoundsException e) {  //数组下标越界
			// TODO: handle exception
			logger.error(e.getMessage());
			e.printStackTrace();
		}
	}

}