List

package com.czie.iot1913.lps.List;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/**
 * @author 1944900433@qq.com
 * @date 2022-03-17 13:43
 */
public class ListDemo01 {
    public static void main(String[] args) {
        //创建集合对象
        List<String> list = new ArrayList<String>();
        //添加元素
        list.add("hello");
        list.add("world");
        list.add("java");
        list.add("java");
        //输出集合对象
        //System.out.println(list);

        //迭代器遍历
        Iterator<String> ite = list.iterator();
        while (ite.hasNext()) {
            String s = ite.next();
            System.out.println(s);
        }
    }
}

package com.czie.iot1913.lps.List;

import java.util.ArrayList;
import java.util.List;

/**
 * @author 1944900433@qq.com
 * @date 2022-03-17 13:49
 */
public class ListDemo02 {
    public static void main(String[] args) {
        //创建集合对象
        List<String> list = new ArrayList<String>();
        //添加元素
        list.add("hello");
        list.add("world");
        list.add("java");
//void add(String item)
//将指定的项目添加到滚动列表的结束时。
        list.add(2, "javaee");
        //list.add(20,"javaee");
        //IndexOutOfBoundsException

//void remove(String item)
//从列表中移除项目的第一个发生。
        System.out.println(list.remove(1));
        System.out.println(list.remove("javaee"));
        //System.out.println(list.remove(11));

//E set(int index, E element)
// 修改指定索引的元素 返回被修改的元素
        System.out.println(list.set(1, "javaee"));
        //System.out.println(list.set(1,"javaee"));

//E get(int index)
// 返回指定索引的元素
        System.out.println(list.get(0));
        //System.out.println(list.get(10));
        //IndexOutOfBoundsException
        System.out.println("=======");

        //输出集合对象
        //System.out.println(list);

        //遍历集合
        for (int i = 0; i < list.size(); i++) {
            System.out.println(list.get(i));
        }

    }
}

package com.czie.iot1913.lps.List;

import java.util.ArrayList;
import java.util.List;

/**
 * @author 1944900433@qq.com
 * @date 2022-03-17 14:51
 */
public class ListDemo03 {
    public static void main(String[] args) {
        List<String> list = new ArrayList<String>();
        list.add("hello");
        list.add("world");
        list.add("java");
        //遍历集合 看看有没有“world”这个元素 如果有就添加一个javaee元素 请用代码实现
        /*Iterator<String> it = list.iterator();
        while (it.hasNext()){
            String s = it.next();
            if (s.equals("world")){
                list.add("javase");
            }
        }
        //ConcurrentModificationException 此异常可能会被抛出的方法，已检测到的对象的并发修改时，这样的修改是不允许的。*/

        for (int i = 0; i < list.size(); i++) {
            String s=list.get(i);
            if (s.equals("world")){
                list.add("javaee");
            }
        }

        System.out.println(list);

    }
}

package com.czie.iot1913.lps.List;

import java.util.ArrayList;
import java.util.List;
import java.util.ListIterator;

/**
 * @author 1944900433@qq.com
 * @date 2022-03-17 15:55
 */
public class ListIteratorTest01 {
    public static void main(String[] args) {
        List<String> list = new ArrayList<String>();
        list.add("h");
        list.add("e");
        list.add("llo");
//        ListIterator<String> slt = list.listIterator();
//        while (slt.hasNext()){
//            String s=slt.next();
//            System.out.println(s);
//        }
//        System.out.println("----------");
//        //倒叙表达
//        while (slt.hasPrevious()){
//            System.out.println(slt.previous());
//
//        }
        //获取列表迭代器
        ListIterator<String> lit = list.listIterator();
        while (lit.hasNext()){
            String s = lit.next();
            if (s.equals("h")){
                lit.add("javase");
            }
        }
        System.out.println(list);


    }
}

package com.czie.iot1913.lps.List;

/**
 * @author 1944900433@qq.com
 * @date 2022-03-17 14:05
 */
public class Student {
    private String name;
    private int age;

    public Student() {
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = 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;
    }
}

package com.czie.iot1913.lps.List;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/**
 * @author 1944900433@qq.com
 * @date 2022-03-17 14:05
 */
public class StudentListDemo {
    public static void main(String[] args) {
        List<Student> c = new ArrayList<Student>();
        Student s1 = new Student("刘品水",21);
        Student s2 = new Student("常雯君",22);
        Student s3 = new Student("殷泽风",20);
        c.add(s1);
        c.add(s2);
        c.add(s3);
        Iterator<Student> it = c.iterator();
        while (it.hasNext()){
            Student s0=it.next();
            System.out.println(s0.getName()+","+s0.getAge());
        }

        System.out.println("===");
        for (int i = 0; i < c.size(); i++) {
            Student s=c.get(i);
            System.out.println(s.getName()+","+s.getAge());
        }

    }
}