java删除指定索引元素

We have to create a List and add objects/elements to the List and given indexes in java.

我们必须创建一个List并将对象/元素添加到该List中，并在Java中添加给定的索引。

To add any object/element at given index to the List, we use, List.add() method - which is a method of List and used to inserts object/element at given index.

要将给定索引处的任何对象/元素添加到List，我们使用List.add()方法-这是List的一种方法，用于在给定索引处插入对象/元素。

Syntax:

句法：

    List.add(index, element);

Here,

这里，

• index is the position of the list, where we have to insert the element

  index是列表的位置，我们必须在其中插入元素

• element is the value or any object that is to be added at given index

  element是要在给定索引处添加的值或任何对象

Example:

例：

    L.add(0,10);  //adds 10 at 0th index
L.add(1,20);  //adds 20 at 1st index
L.add(3,30);  //adds 30 at 2nd index

Program:

程序：

Here, we are creating a list of integer named int_list with some of the initial elements and we will add some of the elements at given indexes.

在这里，我们将创建一个名为int_list的整数列表， 其中包含一些初始元素，并将在给定索引处添加一些元素。

import java.util.*;
public class ListExample {public static void main (String[] args) {//creating a list of integers
List<Integer> int_list = new ArrayList<Integer> ();
//adding some of the elements
int_list.add (10);
int_list.add (20);
int_list.add (30);
int_list.add (40);
int_list.add (50);
//printing the empty List
System.out.print ("int_list= ");
System.out.println (int_list);
//adding elements by specifying index
int_list.add (0, 5); //will add 5 at 0th index
int_list.add (3, 7); //will add 7 at 3rd index
//printing thed list
System.out.print ("int_list= ");
System.out.print (int_list);
}
};

Output

输出量

int_list= [10, 20, 30, 40, 50]
int_list= [5, 10, 20, 7, 30, 40, 50]

翻译自: https://www.includehelp.com/java-programs/add-object-element-to-the-list-at-specified-index-in-java.aspx

java删除指定索引元素