How to Get Previous and Next Index Using Java ListIterator

In this example we will show how to get previous and next index while traversing through elements of ArrayList with ListIterator in Java.

Source Code

package com.beginner.examples;

import java.util.ArrayList;
import java.util.ListIterator;

public class GetPreviousAndNextIndexListIterator {

	public static void main(String[] args) {
		
		//create ArrayList.
		ArrayList arrayList = new ArrayList();
		
		arrayList.add("A");
		arrayList.add("B");
		arrayList.add("C");
		arrayList.add("D");
		
		//Get an object of ListIterator using listIterator() method.
		ListIterator listIterator = arrayList.listIterator();
		
		/*
		 * Use nextIndex and previousIndex methods of ListIterator to get next and 
		 * previous index from the current position in the list.
		 */
		System.out.println("Previous Index is : " + listIterator.previousIndex());
		System.out.println("Next Index is : " + listIterator.nextIndex());
		
		//advance current position by one using next method.
		listIterator.next();
		System.out.println("Previous Index is : " + listIterator.previousIndex());
		System.out.println("Next Index is : " + listIterator.nextIndex());
	}

}

Output:

Previous Index is : -1
Next Index is : 0
Previous Index is : 0
Next Index is : 1

References

Imported packages in Java documentation:

• List
• ListIterator
• ArrayList