工作內容：

1.集合學習

2.泛型學習

學習分享：

1.典型泛型集合List<T>，HashMap<K,V>

常用定義泛型集合：

List<T> list = new ArrayList<T>();

【儲存型別必須是T型別，可以用Object,來使用這樣就可以儲存所有型別物件，拿出來時需要強制轉型】

Map<K,V> map = new HashMap<K,V>();

【K是鍵值(Key)，V是值(Values)，可以通過map.put()來新增成員，通過String str =  map.get(鍵值);來獲取鍵值相應的值】

Map例項：

//Map的基礎使用
import java.util.HashMap;
import java.util.Map;

public class MapTest {
	public static void main(String[] args) {
		String[] names = { "花兒", "小花", "喊我" };
		String[] ifo = { "小女孩", "小狗", "大班", "年輕人" };
		Map<String, String> map = new HashMap<String, String>();
		for (int i = 0; i < names.length; i++) {
			map.put(names[i], ifo[i]);
		}
		String ifoString = map.get("小花");
		System.out.println(ifoString);
	}
}
 

//List基礎使用
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Vector;

public class ListTest {
	static Pet cat2;
	static List<Pet> pets;
	public static void main(String[] args) {
		pets = new ArrayList<Pet>();
		Pet cat1 = new Pet("小貓", "貓");
		cat2 = new Pet("大貓", "貓");
		Pet cat3 = new Pet("老貓", "貓");
		Dog dog1 = new Dog("小黃", "我餓了");
		Dog dog2 = new Dog("小白", "我餓了");
		Dog dog3 = new Dog("小金", "我餓了");
		pets.add(cat1);
		pets.add(cat2);
		pets.add(cat3);
		ArrayList<Object> list = new ArrayList<Object>();
		list.add(cat1);
		list.add(dog1);
		list.add(dog2);
		list.add(cat2);
		list.add(cat3);
		list.add(dog3);
		for (int i = 0; i < list.size(); i++) {
			if (list.get(i) instanceof Pet) {
				Pet p1 = (Pet) list.get(i);
				System.out.println(p1.name + ":" + p1.type);
			} else {
				Dog dog = (Dog) list.get(i);
				System.out.println(dog.name + ":" + dog.say);
			}
		}
		for (Pet p : pets) {
			if (p.name.equals("大貓")) {
				System.out.println(p.name + ":" + p.type);
			}
		}
		search(pets);
		Iterator<Pet> iterator = pets.iterator();
		while (iterator.hasNext()) {
			Pet pet = (Pet) iterator.next();
			System.out.println(pet.name + "::" + pet.type);
		}

	}

	public static <T> void search(T t) {
		Vector<Pet> vPets = new Vector<>();
		vPets.addAll(pets);
		if (vPets.contains(cat2)) {
			System.out.println("存在cat2");
		}
		System.out.println(vPets);
	}
}