listing continued class bankapp public static void main(string[argsbankaccount ba new bankaccount( )/create acct system out print("before transactions")ba display()/display balance ba deposit( )ba withdraw( )/make deposit /make withdrawal system out print("after transactions")ba display()/display balance /end main(/end class bankapp here' the output from this programbefore transactionsbalance= after transactionsbalance= there are two classes in bank java the first onebankaccountcontains the fields and methods for our bank account we'll examine it in detail in moment the second classbankappplays special role the bankapp class to execute the program in listing from an ms-dos promptyou type java bankapp following the cpromptc:\>java bankapp this command tells the java interpreter to look in the bankapp class for the method called main(every java application must have main(methodexecution of the program starts at the beginning of main()as you can see in listing (you don' need to worry yet about the string[args argument in main(the main(method creates an object of class bankaccountinitialized to value of which is the opening balancewith this statementbankaccount ba new bankaccount( )/create acct