Java中List集合的三种遍历⽅式(全⽹最详)
介绍3种⽅式遍历list集合
1 创建⼀个model
public class News{
private int id;
private String title;
private String author;
public News(int id, String title, String author) {
super();
this.id = id;
this.title = title;
this.author = author;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
}
 ⽅式⼀第⼀种、最基础的遍历⽅式:for循环,指定下标长度,使⽤List集合的size()⽅法,进⾏for循环遍历
import java.util.ArrayList;
public class Demo01 {
  public static void main(String[] args) {
   ArrayList<News> list = new ArrayList<News>();
   list.add(new News(1,"list1","a"));
   list.add(new News(2,"list2","b"));
   list.add(new News(3,"list3","c"));
   list.add(new News(4,"list4","d"));
   for (int i = 0; i < list.size(); i++) {
News s = ((i);
System.out.Id()+"  "+s.getTitle()+"  "+s.getAuthor());
    }
  }
}
  第⼆种、较为简洁的遍历⽅式:使⽤foreach遍历List,但不能对某⼀个元素进⾏操作(这种⽅法在遍历数组和Map集合的时候同样适⽤)
java中字符串转数组
import java.util.ArrayList;
public class Demo02 {
  public static void main(String[] args) {
    ArrayList<News> list = new ArrayList<News>();
     list.add(new News(1,"list1","a"));
     list.add(new News(2,"list2","b"));
     list.add(new News(3,"list3","c"));
     list.add(new News(4,"list4","d"));
    for (News s : list) {
System.out.Id()+"  "+s.getTitle()+"  "+s.getAuthor());
   }
  }
}
  第三种、适⽤迭代器Iterator遍历:直接根据List集合的⾃动遍历import java.util.ArrayList;
public class Demo03 {
  public static void main(String[] args) {
   ArrayList<News> list = new ArrayList<News>();
   list.add(new News(1,"list1","a"));
   list.add(new News(2,"list2","b"));
   list.add(new News(3,"list3","c"));
   list.add(new News(4,"list4","d"));
Iterator<News> iter = list.iterator();
while (iter.hasNext()) {
News s = (News) ();
System.out.Id()+"  "+s.getTitle()+"  "+s.getAuthor());
    }
  }
}

版权声明:本站内容均来自互联网,仅供演示用,请勿用于商业和其他非法用途。如果侵犯了您的权益请与我们联系QQ:729038198,我们将在24小时内删除。