Java Program to Remove elements from the LinkedList.

Example 1: Remove element using remove()

import java.util.LinkedList;

class Main {
  public static void main(String[] args) {
    LinkedList<String> languages = new LinkedList<>();

    // add elements in LinkedList
    languages.add("Java");
    languages.add("Python");
    languages.add("JavaScript");
    languages.add("Kotlin");
    System.out.println("LinkedList: " + languages);

    // remove elements from index 1
    String str = languages.remove(3);
    System.out.println("Removed Element: " + str);

    System.out.println("Updated LinkedList: " + languages);
  }
}

Output

LinkedList: [Java, Python, JavaScript, Kotlin]
Removed Element: Kotlin
Updated LinkedList: [Java, Python, JavaScript]

In the above example, we have created a linkedlist named languages. Here, the remove() method to remove an element from the linkedlist.

The method takes the index number of the element as its parameter.

Example 2 Using listIterator() Method

We can also the listsIterator() to remove elements from the linkedlist.

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

class Main {
    public static void main(String[] args) {
        ArrayList<String> animals= new ArrayList<>();

        // add elements
        animals.add("Dog");
        animals.add("Cat");
        animals.add("Horse");
        System.out.println("LinkedList: " + animals);

        // creating an object of ListIterator
        ListIterator<String> listIterate = animals.listIterator();
        listIterate.next();

        // चemove element returned by next()
        listIterate.remove();
        System.out.println("New LinkedList: " + animals);
    }
}

Output

LinkedList: [Dog, Cat, Horse]
New LinkedList: [Cat, Horse]

In the above example, the listIterator() method returns an iterator to access each element of the linkedlist.

Here, the next() method returns the next element in the linkedlist.

Example 3: Remove all elements using clear()

We can use the clear() method to remove all the elements of a linkedlist.

import java.util.LinkedList;

class Main {
  public static void main(String[] args) {
    LinkedList<String> languages = new LinkedList<>();

    // add elements in LinkedList
    languages.add("Java");
    languages.add("Python");
    languages.add("Swift");
    System.out.println("LinkedList: " + languages);

    // remove all the elements
    languages.clear();
    System.out.println("LinkedList after clear(): " + languages);
  }
}

Output

LinkedList: [Java, Python, Swift]
LinkedList after clear(): []

Note: We can also use the removeAll() method to remove all the elements. However, the clear() method is considered more efficient than the removeAll() method.

Example 4: Using the removeIf() Method

We can also remove elements from a linkedlist if they satisfied a certain condition. For this, we use the removeIf() method.

import java.util.LinkedList;

class Main {
  public static void main(String[] args) {
    LinkedList<Integer> numbers = new LinkedList<>();

    // add elements in LinkedList
    numbers.add(2);
    numbers.add(3);
    numbers.add(4);
    numbers.add(5);
    System.out.println("LinkedList: " + numbers);

    // remove all elements less than 4
    numbers.removeIf((Integer i) -> i < 4);
    System.out.println("Updated LinkedList: " + numbers);

  }
}

Output

LinkedList: [2, 3, 4, 5]
Updated LinkedList: [4, 5]

In the above example, (Integer i) -> i < 4 is a lambda expression. To learn more about lambdas, visit Java Lambda Expression. It returns the number less than 4.

The removeIf() method removes the number returned by the lambda expression.