Java中List集合的三种遍历方式(全网最详)

List集合在Java日常开发中是必不可少的，只要懂得运用各种各样的方法就可以大大提高我们开发的效率，适当活用各种方法才会使我们开发事半功倍。

我总结了三种List集合的遍历方式，下面一一来介绍。

首先来创建一个实体类，以供下面使用。

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;

}

}

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 list = new ArrayList(); 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 = (News)list.get(i);

System.out.println(s.getId()+" "+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）

import java.util.ArrayList;

public class Demo02 {

public static void main(String[] args) {

ArrayList list = new ArrayList();

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.println(s.getId()+" "+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 list = new ArrayList();

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 iter = list.iterator();

while (iter.hasNext()) {

News s = (News) iter.next();

System.out.println(s.getId()+" "+s.getTitle()+" "+s.getAuthor());

}

}

}

上面三种遍历方式差别不是特别大，在没有特定的要求时，均可以使用。不过根据不同的特殊情况，要合理选择方式，来提高开发的效率。