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.