listing continued thelist displaylist()///end class linkqueue ///////////////////////////////////////////////////////////////class linkqueueapp public static void main(string[argslinkqueue thequeue new linkqueue()thequeue insert( )/insert items thequeue insert( )thequeue displayqueue()/display queue thequeue insert( )thequeue insert( )/insert items thequeue displayqueue()/display queue thequeue remove()thequeue remove()/remove items thequeue displayqueue()/end main(/display queue ///////////////////////////////////////////////////////////////the program creates queueinserts two itemsinserts two more itemsand removes two itemsfollowing each of these operations the queue is displayed here' the outputqueue (front-->rear) queue (front-->rear) queue (front-->rear) here the methods insert(and remove(in the linkqueue class are implemented by the insertlast(and deletefirst(methods of the firstlastlist class we've substituted linked list for the array used to implement the queue in the queue java program (listing of the linkstack java and linkqueue java programs emphasize that stacks and queues are conceptual entitiesseparate from their implementations stack can be implemented equally well by an array or by linked list what' important about stack is