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LinkedList in Java

/* LinkedList is a linked list implementation of the List interface.
 * Implements all optional list operations, and permits all elements (including null).
 * In addition to implementing the List interface, the LinkedList class provides uniformly named methods to get,
 * remove and insert an element at the beginning and end of the list.
 * These operations allow linked lists to be used as a stack, queue, or double-ended queue.
 */


package collection.list;

import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

public class LinkedListDemo {
    public LinkedListDemo() {
        super();
    }
   
    public static void main(String[] args){
/* Linked list simple example
 * LinkedList of type String
*/
        simpleLinkedList();

/* LinkedList emaple with Employee class objects
 * with sorting, iterating in forward and backword direction
 */
        LinkedList<Employee> employee = employeeLinkedList();
        linkedListOperations(employee);
       
    }
   
    public static LinkedList<Employee> employeeLinkedList(){
        LinkedList<Employee> employee= new LinkedList<Employee>();
        employee.add(new Employee(12,"Bipasha","AB+"));  
        employee.add(new Employee(25,"Kenith","B+"));
        employee.add(new Employee(82,"Alia","A-"));
        employee.add(new Employee(41,"Priti","AB-"));
        employee.add(new Employee(20,"John","B-"));
        employee.add(new Employee(89,"Khali","AB-"));
        Iterator iterator = employee.iterator();
        while(iterator.hasNext()){
            System.out.println(iterator.next());
        }
        Collections.sort(employee);
       
        System.out.println("\n\nEmployee's after sorting by id in ascending order");
        Iterator iter = employee.iterator();
        while(iter.hasNext()){
            System.out.println(iter.next());
        }
       
        System.out.println("\n\nEmployee's after sorting by id in descending order");
        Iterator descItr = employee.descendingIterator();
            while(descItr.hasNext()){
                System.out.println(descItr.next());
            }
        return employee;
    }
   
    public static void simpleLinkedList(){
        System.out.println("Enter");
        List<String> linkedList= new LinkedList<String>();
        linkedList.add("Hey");
        linkedList.add("How");
        linkedList.add("Are");
        linkedList.add("You");
        linkedList.add("Dude");
        Iterator itr = linkedList.iterator();
        while(itr.hasNext()){
            System.out.println(itr.next());
        }
        System.out.println(linkedList);
    }

    private static void linkedListOperations(LinkedList<Employee> employee) {
        System.out.println("\n\nAdding Employee in LinkedList");
        employee.add(new Employee(100,"Rockstar","A+"));
        for(Employee list : employee){
            System.out.println(list);
        }
       
        System.out.println("\n\nRemoving Employee in LinkedList");
        for(Employee emp:employee){
            if(emp.getEmpId()==25){
                employee.remove(emp);
                System.out.println("Employee id : 25 deleted");
                break;
            }
        }
        System.out.println("\n\nAfter shuffling LinkedList");
        Collections.shuffle(employee);
        for(Employee list : employee){
            System.out.println(list);
        }
    }
}

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