CPE 5009 Mock Exam

1. (General concepts)
   • What are the differences and similarities between synchronous and asynchronous processes?
   • Give some examples of where each can be used
2. (Service specification in Java)
   Your letterbox/mailbox at your house/flat has a variety of sensors that can tell what it contains and what is put into it. It can tell the difference between junk mail and mail addressed to you.
   • Write a Java interface for your mailbox as a service: it will call methods when new mail/junkmail has arrived, and can respond to queries about what mail it contains.
   • Which of the methods need listener lists, and which are called directly by remote objects?
   • Are there any security/privacy issues which should be handled by your mailbox?
3. (Multiple service interaction)
   

   Your smart filing cabinet has a number of drawers neatly labelled; "current units", "previous units", "tax and immigration issues" and "other". Each draw contains smart folders, which know their label (e.g. "CPE 5009") and a list of documents they contain. The filing cabinet owner will want to browse folders, search for specific folders, browse folders and search for documents within a folder. In addition, they will want to make new folders and add documents to folders.

   Draw diagram(s) showing user, cabinet and folders, and messages that would be sent between all three

4. (MIDP)
   Write a MIDP program for the user to browse the filing cabinet, select a drawer and browse the drawer for folders. Once a folder is selected, the program should display the titles of the documents in the folder
5. (Service references and mobile objects)
   

   To clean your clothes every week you have to go to the local laundromat. But you only want to go there if you know that a washing machine is free, otherwise you will be wasting time. So you want to be able to ask the laundromat if it has free machines. If it does not currently have any washing machines free, you want to be placed on a list to be informed when one is available. When a washing machine becomes free, you want to book it for the next 10 minutes.

   Using ordinary Java objects and RMI proxy objects, show the Java objects and methods needed to implement such a system between yourself, the laundromat and an available washing machine. Do this using UML diagrams or Java classes, showing attributes and method signatures. Do not write any method implementations

6. (Service vs attribute information)