Linked List in Java

Linked List in Java

• It is based on linear data structure in storage. Not a continuous storage.
• It is implements List and Queue interface in java.
• It store the elements using separate object for address and data part.
• It also returns the element in insertion order.
• It allows null and duplicate elements also.
• It uses the doubly linked list process to store elements
• Doubly linked list having collection of nodes. Such as data node, next node, previous node.

Creating Linked List:

Linked List obj=new Linked List ();

Linked List obj=new Linked List(Collection c);

Methods:

boolean add(E)

E – Element
It is used add a element in last in the list

void add(int,E)

int – index of the element , E –Element
It is used to add element in particular index

void addFirst(E)

E – Element
It is used to add element in first in the list.

void addLast(E)

E – Element
It is used to add element in last in the list.

void offerFirst(E)

E – Element
It is used to add element in front of queue or list.

void offerLast(E)

E – Element
It is used to add element in end of queue or list.

E getFirst()

It is used to get the first element in the list.

E getLast()

It is used to get the last element in the list.

E removeFirst()

It used to remove and returns the first element in the list.

E removeLast()

It used to remove and returns the last element in the list.

E removeFirstOccurence(Object e)

It used to remove and returns the first occurrence of the specified element in list.

E removeLastOccurence(Object e)

It used to remove and returns the last occurrence of the specified element in list.
Example:

public class LinkedListExample {
public static void main(String[] args) {
LinkedList obj=new LinkedList();
obj.add("hello");
obj.add(1, "hell");
obj.addFirst("welcome");
obj.addLast("world");
obj.offerFirst("happy");
obj.offerLast("sad");
System.out.println("Linked list : " + obj);
System.out.println("Get the First Element : " + obj.getFirst());
System.out.println("Get the Last Element : " + obj.getLast());
obj.removeFirst();
System.out.println("Linked list : " + obj);
obj.removeLast();
System.out.println("Linked list : " + obj);
obj.remove("hell");
System.out.println("Linked list : " + obj);
}
}