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Java ArrayList lastlastIndexOf() Method with Example

ArrayList Class lastIndexOf() method: Here, we are going to learn about the lastIndexOf() method of ArrayList Class with its syntax and example.
Submitted by Preeti Jain, on January 18, 2020

ArrayList Class lastIndexOf() method

• lastIndexOf() method is available in java.util package.
• lastIndexOf() method is used to return the index of the last occurrence of the given object in this Arraylist.
• lastIndexOf() method is a non-static method so it is accessible with the class object and if we try to access the method with the class name then we will get an error.
• lastIndexOf() method does not throw an exception at the time of returning the index of the last occurrence of the given element.

Syntax:

     public int lastIndexOf(Object obj);

Parameter(s):

• Object obj – represents the object to search for the last index.

Return value:

The return type of the method is int, it returns the index of the last occurrence of the given object in this Arraylist otherwise it returns -1 when the given object does not exist in this Arraylist.

Example:

// Java program to demonstrate the example 
// of int lastIndexOf(int) method of ArrayList.

import java.util.*;

public class LastIndexOfArrayList {
    public static void main(String[] args) {
        // Create an ArrayList with initial 
        // capacity of storing elements

        ArrayList < String > arr_l = new ArrayList < String > (10);

        // By using add() method is to add 
        // elements in this ArrayList

        arr_l.add("C");
        arr_l.add("C++");
        arr_l.add("JAVA");
        arr_l.add("DOTNET");
        arr_l.add("PHP");
        arr_l.add("JAVA");

        // Display ArrayList
        System.out.println("ArrayList Elements :" + arr_l);

        // By using lastIndexOf(Object) method is to
        // return the index of the last occurrence
        // of the given Object in this ArrayList

        int index = arr_l.lastIndexOf("JAVA");

        // Display Index 
        System.out.println("arr_l.lastIndexOf(JAVA) : " + index);
    }
}

Output

ArrayList Elements :[C, C++, JAVA, DOTNET, PHP, JAVA]
arr_l.lastIndexOf(JAVA) : 5