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Java LinkedList boolean removeFirstOccurrence(Object o) method with Example

Java LinkedList boolean removeFirstOccurrence(Object o) method: Here, we are going to learn about the boolean removeFirstOccurrence(Object o) method of LinkedList class with its syntax and example.
Submitted by Preeti Jain, on June 25, 2019

LinkedList boolean removeFirstOccurrence(Object o) method

• This method is available in package java.util.LinkedList.removeFirstOccurrence(Object o).
• This method is used to remove the first occurrence of the specified object from the linked list and when we traverse LinkedList from beginning to end (Head to Tail).

Syntax:

    boolean removeFirstOccurrence(Object o){
    }

Parameter(s):

We can pass only one object as a parameter in the method and that object will remove first occurrence of the specified object from the linked list.

Return value:

The return type of this method is boolean that means this method returns true after execution.

Java program to demonstrate example of LinkedList removeFirstOccurrence() method

Case 1: How boolean removeFirstOccurrence(Object o) method works without duplicate objects in the LinkedList?

import java.util.LinkedList;

public class LinkList {
    public static void main(String[] args) {
        LinkedList list = new LinkedList();
        // use add() method to add few elements in the list 
        list.add(50);
        list.add(60);
        list.add(70);
        list.add(80);
        list.add(90);

        //  Current list Output
        System.out.println("The Current list is:" + list);

        // Remove one element of index 3(i.e 80) from the list 
        list.removeFirstOccurrence(80);

        //  New list Output 
        System.out.println("The new List is:" + list);
    }
}

Output

D:\Programs>javac LinkList.java

D:\Programs>java LinkList
The Current list is:[50, 60, 70, 80, 90]
The new List is:[50, 60, 70, 90]

Case 2: How boolean removeFirstOccurrence(Object o) method works with duplicate objects in the list?

import java.util.LinkedList;

public class LinkList {
    public static void main(String[] args) {
        LinkedList list = new LinkedList();
        // use add() method to add few elements in the list 
        list.add("J");
        list.add("A");
        list.add("V");
        list.add("A");
        list.add("L");
        list.add("A");
        list.add("N");
        list.add("G");
        list.add("U");
        list.add("A");
        list.add("G");
        list.add("E");

        //  Current list Output
        System.out.println("The Current list is:" + list);

        // Remove one elements from the list and here G comes two times 
        // in a list so it will remove first occurrence of  G will remove from the list 
        list.removeFirstOccurrence("G");

        //  New list Output 
        System.out.println("The new List is:" + list);
    }
}

Output

D:\Programs>javac LinkList.java

D:\Programs>java LinkList
The Current list is:[J, A, V, A, L, A, N, G, U, A, G, E]
The new List is:[J, A, V, A, L, A, N, U, A, G, E]