28_List接口、ArrayList类、Iterator遍历 、Collections排序

package coms;

import java.util.*;
/**
 * List接口
 * ArrayList类
 * Iterator遍历  
 * Collections.sort(l);排序
 * Comparable接口
 * @author user
 *
 */
public class javalx34 {

    public static void main(String[] args) {
        String s1=new String("-liu");
        String s2=new String("-zhang");
        String s3=new String("-wang");
        String s4=new String("-li");
        String s5=new String("-sun");
        String s6=new String("-hui");
        List<String> l = new ArrayList<String>();
        l.add(s1);
        l.add(s2);
        l.add(s3);//添加
        l.add(s4);
        l.add(s5);
        l.add(s6);
        l.remove(1);//删除
        System.out.println(l.size());//长度
        System.out.println(l.contains(s2));//判断是否包含S2
        System.out.println(l.get(0));//获取第一个对象
        
        Studento a=new Studento(2, "liu--", 22);
        Studento b=new Studento(3, "zhang--",23);
        Studento c=new Studento(4, "liu--", 24);
        Studento d=new Studento(1, "zhang--",21);
        List<Studento> ls=new ArrayList<Studento>();
        ls.add(a);
        ls.add(b);
        ls.add(c);
        ls.add(d);
        Collections.sort(ls);
        Iterator<Studento> j=ls.iterator();
        while(j.hasNext()){
            System.out.println(((Studento)j.next()).getId());
        }
        
        Collections.sort(l);//排序
        Iterator<String> i=l.iterator();//iterator遍历
        while(i.hasNext()){
            System.out.print(i.next());
        }
    }
}

class Studento implements Comparable<Object>{
    private int id;
    private String name;
    private int age;
    
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public Studento(int id,String name,int age){
        this.name=name;
        this.age=age;
        this.id=id;
    }
    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;
    }
    
    
    //覆盖方法
    public int compareTo(Object o){
        Studento s=(Studento)o;
        if(this.id<s.id)return -1;
        else if(this.id==s.id) return 0;
        else return 1;
    }

}