The Linkedlist class

  • The Linked list class extends abstract sequential list and implements the list interface.
  • It provides a linked list data structure.
  • It has two constructors are shown below.
  1. Linked List():( It builds an empty linked list
  2. Linked List (collecton c): this constructor builds a linked list that is initialized with elements of the collection c.
  • In addition to the methods that it inherits, the linked list class defines some useful methods of its own, as shown below, for manipulating and accessing lists.

Voids addfirst (object obj):

In this adds elements to the start of the list.

Voids addlast (object obj):

In this adds elements to the last of the list.

Object getfirst ():

Returns the first element present in the list

Object getlast ():

Retrieves the last element from the list

Object removefirst ():

Removes or deletes the first element from the list

Object removelast ():

Removes the last element from the last

The following program illustrates several of the methods supported by the linked list.

Example program:

Import java. Util.*;

Class linked List Demo

{

Public static void main (string args [ ])

{

Linked List   ll = new linked list ();

ll. add ( “ MSD”);

ll. add ( “ SSA”);

ll. add ( “ MGR”);

ll. add ( “ PV”);

ll. add ( “ PS”);

ll. add  last ( “ MSK”);

ll. add  first ( “ MSS”);

ll. add ( 3,“ MSR”);

System. Out. Prinln(“ contents of list :” +ll);

ll. remove (“ PV”);

ll.remove (4);

System. Out. Prinln(“ contents of list, after deletion :” +ll);

ll. remove first();

ll. remove last ();

System. Out. Prinln(“ after removing first and last elements :” +ll);

Object value = ll.get (1);

ll.set (1, (string) value+ “MSD”);

System. Out. Prinln(“list, after modifications:” +ll);

}

}

  • The output of the above program is as shown below.
  1. Contents of the list: MSS MSD SSA MSR PS MSK
  2. CONTENTS OF THE LIST AFTER DELETION:  MSS MSD MSR PS MSK
  3. After removing first and last elements: MSD SSA MSR PS
  4. List after modification: MSD SSA MSD MSR PS.

 

The Linkedlist Class Homework Help