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# Java `ArrayList add(int index, E element)` > 原文: [https://beginnersbook.com/2013/12/java-arraylist-addint-index-e-element-example/](https://beginnersbook.com/2013/12/java-arraylist-addint-index-e-element-example/) 简单的[`add()`方法](https://beginnersbook.com/2013/12/java-arraylist-add-method-example/)用于在列表的末尾添加元素,但是`add`方法的另一种变体用于向指定的索引添加元素。 `public void add(int index, Object element)` 此方法在给定索引处添加元素。 ### 例 ```java package beginnersbook.com; import java.util.ArrayList; public class AddMethodExample { public static void main(String[] args) { // ArrayList of String type ArrayList<String> al = new ArrayList<String>(); // simple add() methods for adding elements at the end al.add("Hi"); al.add("hello"); al.add("String"); al.add("Test"); //adding element to the 4th position //4th position = 3 index as index starts with 0 al.add(3,"Howdy"); System.out.println("Elements after adding string Howdy:"+ al); //adding string to 1st position al.add(0, "Bye"); //Print System.out.println("Elements after adding string bye:"+ al); } } ``` 输出: ```java Elements after adding string Howdy:[Hi, hello, String, Howdy, Test] Elements after adding string bye:[Bye, Hi, hello, String, Howdy, Test] ``` #### 参考 [`ArrayList.add(int,E)`](https://docs.oracle.com/javase/6/docs/api/java/util/ArrayList.html#add(int, E))