Implementation of Java LinkedList class

Java LinkedList: add() and size() methods

KW.java

import java.util.LinkedList;

class KW 
{
    public static void main(String[] args) 
    {
        //LinkedList class implements the List interface and Deque -> Queue interface
        LinkedList<String> ll=new LinkedList<>();
        ll.add("Apple");
        ll.add("Orange");
        ll.add("Mango");
        ll.add("Grapes");
        ll.add("Cherry");
        ll.add("Apple");
        System.out.println(ll);
        System.out.println("Size: "+ll.size());
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Orange, Mango, Grapes, Cherry, Apple]
Size: 6
kodingwindow@kw:~$

Java LinkedList: get() and contains() methods

KW.java

import java.util.LinkedList;

class KW 
{
    public static void main(String[] args) 
    {
        //LinkedList class implements the List interface and Deque -> Queue interface
        LinkedList<String> ll=new LinkedList<>();
        ll.add("Apple");
        ll.add("Orange");
        ll.add("Mango");
        ll.add("Grapes");
        ll.add("Cherry");
        ll.add("Apple");
        for(String s:ll)
        {
            System.out.println(s);
        }
        System.out.println("\n"+ll.get(3));
        System.out.println(ll.contains("Apple"));
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
Apple
Orange
Mango
Grapes
Cherry
Apple

Grapes
true
kodingwindow@kw:~$

Java LinkedList: addFirst() and addLast() methods

KW.java

import java.util.LinkedList;

class KW 
{
    public static void main(String[] args) 
    {
        //LinkedList class implements the List interface and Deque -> Queue interface
        LinkedList<String> ll=new LinkedList<>();
        ll.add("Apple");
        ll.add("Orange");
        ll.add("Mango");
        ll.add("Grapes");
        ll.add("Cherry");
        for(String s:ll)
        {
            System.out.println(s);
        }
        
        ll.addFirst("Strawberry");
        ll.addLast("Apple");
        System.out.println("\n"+ll);
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
Apple
Orange
Mango
Grapes
Cherry

[Strawberry, Apple, Orange, Mango, Grapes, Cherry, Apple]
kodingwindow@kw:~$

Java LinkedList: getFirst() and getLast() methods

KW.java

import java.util.LinkedList;

class KW 
{
    public static void main(String[] args) 
    {
        //LinkedList class implements the List interface and Deque -> Queue interface
        LinkedList<String> ll=new LinkedList<>();
        ll.add("Apple");
        ll.add("Orange");
        ll.add("Grapes");
        ll.add("Cherry");
        ll.add("Apple");
        ll.add("Mango");
        
        System.out.println(ll);
        System.out.println("First element: "+ll.getFirst());
        System.out.println("Last element: "+ll.getLast());
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Orange, Grapes, Cherry, Apple, Mango]
First element: Apple
Last element: Mango
kodingwindow@kw:~$

Java LinkedList: indexOf() and lastIndexOf() methods

KW.java

import java.util.LinkedList;

class KW 
{
    public static void main(String[] args) 
    {
        //LinkedList class implements the List interface and Deque -> Queue interface
        LinkedList<String> ll=new LinkedList<>();
        ll.add("Apple");
        ll.add("Orange");
        ll.add("Mango");
        ll.add("Grapes");
        ll.add("Cherry");
        ll.add("Apple");
        
        System.out.println("indexOf Apple: "+ll.indexOf("Apple"));
        System.out.println("lastIndexOf Apple: "+ll.lastIndexOf("Apple"));
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
indexOf Apple: 0
lastIndexOf Apple: 5
kodingwindow@kw:~$

Java LinkedList: addAll() and containsAll() methods

KW.java

import java.util.LinkedList;

class KW 
{
    public static void main(String[] args) 
    {
        //LinkedList class implements the List interface and Deque -> Queue interface
        LinkedList<String> ll1=new LinkedList<>();
        ll1.add("Apple");
        ll1.add("Orange");
        ll1.add("Mango");
        System.out.println(ll1);
        
        LinkedList<String> ll2=new LinkedList<>();
        ll2.add("Grapes");
        ll2.add("Cherry");
        ll2.add("Apple");
        System.out.println(ll2);
        
        System.out.println(ll1.containsAll(ll2));
        
        ll1.addAll(ll2);
        System.out.println(ll1);
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Orange, Mango]
[Grapes, Cherry, Apple]
false
[Apple, Orange, Mango, Grapes, Cherry, Apple]
kodingwindow@kw:~$

Java LinkedList: remove() and removeAll() methods

KW.java

import java.util.LinkedList;

class KW 
{
    public static void main(String[] args) 
    {
        //LinkedList class implements the List interface and Deque -> Queue interface
        LinkedList<String> ll=new LinkedList<>();
        ll.add("Apple");
        ll.add("Orange");
        ll.add("Mango");
        ll.add("Grapes");
        ll.add("Cherry");
        ll.add("Apple");
        
        System.out.println(ll);
        ll.remove();
        System.out.println(ll);
        ll.remove(2);
        System.out.println(ll);
        ll.remove("Cherry");
        System.out.println(ll);
        
        ll.removeAll(ll); //ll.clear();
        if(ll.isEmpty())
        {
            System.out.println("LinkedList is empty now");
        }
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Orange, Mango, Grapes, Cherry, Apple]
[Orange, Mango, Grapes, Cherry, Apple]
[Orange, Mango, Cherry, Apple]
[Orange, Mango, Apple]
LinkedList is empty now
kodingwindow@kw:~$

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