java深化——各种类型的集合 存储方式的总结代码

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public class Person implements Comparable<Person>{
	private String name;
	private int age;
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	public Person(String name, int age) {
		super();
		this.name = name;
		this.age = age;
	}
	public Person() {
		super();
	}
	@Override
	public String toString() {
		return "Person [name=" + name + ", age=" + age + "]";
	}
	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + age;
		result = prime * result + ((name == null) ? 0 : name.hashCode());
		return result;
	}
	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		Person other = (Person) obj;
		if (age != other.age)
			return false;
		if (name == null) {
			if (other.name != null)
				return false;
		} else if (!name.equals(other.name))
			return false;
		return true;
	}
	@Override
	public int compareTo(Person o) {
		// TODO Auto-generated method stub
		return this.getName().compareTo(o.getName());//按照字母名比较
	}
}

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public class Test {
	public static void main(String[] args) {
		Person p1 = new Person("胡苗青",10);
		
		System.out.println("-----ArrayList存储-----");
		ArrayList<Person> al=new ArrayList<Person>();
		al.add(p1);
		System.out.println(al+"n");
		
		System.out.println("-----LinkedList存储-----");
		LinkedList<Integer> ll = new LinkedList<Integer>();
		ll.add(123);  //123进行了自动装箱
		System.out.println(ll+"n");
		
		System.out.println("-----HashSet存储-----");
		//HashSet存储自定义对象时，要求Person类重写hashCode()与equal()方法
		HashSet<Person> hs = new HashSet<Person>();
		hs.add(p1);
		System.out.println(hs+"n");
		
		System.out.println("-----TreeSet存储-----");
		//TreeSet存储自定义对象时，要求Person类具备比较规则，可以使内部比较器 可以是外部比较器
		TreeSet<Person> ts=new TreeSet<Person>();//implements Comparable<Person>
		ts.add(p1);
		System.out.println(ts+"n");
		
		System.out.println("-----HashMap存储-----");
		//Map集合采用键值对的存储方式
		HashMap<Person,String> hm = new HashMap<Person,String>();
		hm.put(p1, p1.getName());
		System.out.println(hm+"n");
		
		System.out.println("-----TreeMap存储-----");
		TreeMap<Person,Integer> tm = new TreeMap<Person,Integer>();
		tm.put(p1, p1.getAge());
		System.out.println(tm);
	}
}