Prepare a java program to simulate a simple multiuser computer system as follows: Each user has a unique ID and wishes to perform a number of transactions on the the computer. Thus, only one transaction may be processed by the computer at any given moment. Each input line shows a single user and contains the user's ID followed by a starting time and a series of integers representing the duration of each of his or her transactions. The input is sorted by increasing starting time, and all times and durations are in seconds. Consider that a user does not request time for a transaction untill the previous transaction is complete and that the computer accepts transactions on a first-come first-serve basis. The program should simulate the system and print a message containing the users ID and the time whenever a transaction begins to end.

If i get more details, i will send you some more information. This assignment is about queue, priority queues, and Trees if it helps. I am also send some powerpoint slides about that.