listing trees and external storage continued return thenode getchild( )/return right child /public void displaytree(recdisplaytree(root )/private void recdisplaytree(node thisnodeint levelint childnumbersystem out print("level="+level+child="+childnumber+")thisnode displaynode()/display this node /call ourselves for each child of this node int numitems thisnode getnumitems()for(int = <numitems+ ++node nextnode thisnode getchild( )if(nextnode !nullrecdisplaytree(nextnodelevel+ )else return/end recdisplaytree(//end class tree ///////////////////////////////////////////////////////////////class tree app public static void main(string[argsthrows ioexception long valuetree thetree new tree ()thetree insert( )thetree insert( )thetree insert( )thetree insert( )thetree insert( )