/*

 题目：

 （多态，instanceof）有如下代码

class Animal

{

 	private String name;

	// 1

}

class Dog extends Animal

{

	//2

}

class Cat extends Animal

{

	//3

}

public class TestAnimal

{

	public static void main(String args[]){

	Animal[] as = new Animal[]{

	new Dog("Pluto"),

	new Cat("Tom"),

	new Dog("Snoopy"),

	new Cat("Garfield")

};

	Dog[] dogs = getAllDog(as);

	for(int i = 0; i<=dogs.length; i++)

	{

		System.out.println(dogs[i].getName());

	}

}

public static Dog[] getAllDog(Animal[] as)

{

	//4

}

}

程序填空：

a) 在 //1, //2, //3 处填上适当的get/set 方法和构造方法

b) 完成//4 处的填空。getAllDog 方法从一个Animal 数组中挑选出所有的Dog 对象，并把这些对象放在一个Dog 数组中返回。

*/

package MyTest;

class Animal

{

	private String name;

	// 1

	public String getName()

	{

		return this.name;

	}

	public void setName(String name)

	{

		this.name = name;

	}

}

class Dog extends Animal

{

	// 2

	Dog(String name)

	{

		this.getName();

		this.setName(name);

	}

}

class Cat extends Animal

{

	// 3

	Cat(String name)

	{

		this.getName();

		this.setName(name);

	}

}

public class TestAnimal

{

	/*

	 * @param args

	 */

	public static void main(String[] args)

	{

		Animal[] as = new Animal[]

		{

				new Dog("Pluto"),

				new Cat("Tom"),

				new Dog("Snoopy"),

				new Cat("Garfield")

	    };

		Dog[] dogs = getAllDog(as);

		for (int i = 0; i < dogs.length; i++)

		{

			System.out.println(dogs[i].getName());

		}

	}

	public static Dog[] getAllDog(Animal[] as)

	{

		// 4

		Dog[] dog = new Dog[as.length];

		int len = as.length;

		int j = 0;

		for(int i = 0;i<len;i++)

		{

			if(as[i] instanceof Dog)

			{

				dog[j] = (Dog)as[i];

				j++;

			}

		}

		//////////////////

		Dog[] dg = new Dog[j];

		for(int i = 0;i<j;i++)

		{

			dg[i] = dog[i];

		}

		//////////////////

		return dg;

		/*

		 方法二：

		 public static Dog[] getAllDog(Animal[] as)

	     {

		  // 4

			List<Dog>dd = new ArrayList<Dog>();

			for(int i=0; i<as.length; i++)

			{

				//System.out.println(as[i].getClass().getName());

				if (as[i].getClass().getName().contains("Dog"))//( as[i] instanceof Dog )

				{

					dd.add((Dog)as[i]);

				}

			}

			int size = dd.size();

			Dog[] cc = (Dog[])dd.toArray(new Dog[size]);

			return cc;

		}

		*/

	}

}