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how to get first element in linked list in java?


LinkedList:

The LinkedList class extends AbstractSequentialList and implements the List and Deque interface. It uses linked list data structure to store elements. It can contain duplicate elements. It is not synchronized.

Note: It not provides the random access facility.

Following methods are used to get first element in linked list in java:

  • element(): Retrieves, but does not remove, the head (first element) of this list.
  • getFirst(): Returns the first element in this list.
  • peek(): Retrieves, but does not remove, the head (first element) of this list.
  • peekFirst(): Retrieves, but does not remove, the first element of this list, or returns null if this list is empty.

Example:

package com.codesjava;
 
import java.util.LinkedList;
 
public class Test {
  public static void main(String args[]){
	LinkedList<String> linkedList = new LinkedList<String>();
	linkedList.add("Jai");
	linkedList.add("Mahesh");
	linkedList.add("Naren");
	linkedList.add("Vivek");
	linkedList.add("Vishal");
	linkedList.add("Hemant");
	System.out.println("Actual LinkedList:"+linkedList);
	System.out.println("First Element: "+linkedList.element());
        System.out.println("First Element: "+linkedList.getFirst());
        System.out.println("First Element: "+linkedList.peek());
        System.out.println("First Element: "+linkedList.peekFirst());
  }
}

Output

Actual LinkedList:[Jai, Mahesh, Naren, Vivek, Vishal, Hemant]
First Element: Jai
First Element: Jai
First Element: Jai
First Element: Jai


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