Computer Science 225
Advanced Programming

Spring 2017, Siena College

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You will work with a partner on this lab. Only one submission per group is needed.

Getting Set Up

You should have a directory (i.e., folder) in your directory named csis225. Create a directory within csis225 named lab0. Create your BlueJ project for this lab within that folder.

Writing a Simulation Program

Your task is to write a Java program to simulate a series of dice rolls, and report some statistics about them. Specifically, your program should meet these requirements:

• Your program takes two command-line parameters: a file name and an integer.
• The contents of the specified file is a series of positive integers, each of which represents a fair die. Each number indicates the number of sides of the next die.
• The integer is the number of times to roll the dice during the simulation. This number is referred to as n_rolls below.
• Before starting the simulation, report the number of dice and the number of sides in each to standard output.
• Simulate n_rolls dice rolls. For each roll, print the value for each die, and the sum of the roll.
• At the end, report the roll counts (the number of time each number came up) for each die, and the sum counts (the number of times each sum came up), and the average sum across all rolls (printed with 2 digits after the decimal point).
• All errors should be handled gracefully. For example, if an incorrect number of command-line parameters is provided, a nice error message is appropriate; an uncaught exception with a stack trace is not.

For example, if the file dice.txt contains the numbers 6, 8, and 10, and that file is specified as the first command-line parameter and the number 15 is the second command-line parameter, the following is a possible output:

Simulation has 3 fair dice:
  6-sided
  8-sided
  10-sided
Roll 1: 4 4 2 total: 10
Roll 2: 2 4 2 total: 8
Roll 3: 3 1 4 total: 8
Roll 4: 4 7 1 total: 12
Roll 5: 5 1 3 total: 9
Roll 6: 6 8 6 total: 20
Roll 7: 1 7 10 total: 18
Roll 8: 3 3 9 total: 15
Roll 9: 3 2 7 total: 12
Roll 10: 3 3 3 total: 9
Roll 11: 4 7 10 total: 21
Roll 12: 2 1 6 total: 9
Roll 13: 3 1 8 total: 12
Roll 14: 5 6 1 total: 12
Roll 15: 6 3 10 total: 19
Simulation summary:
Roll counts for 6-sided die: 1:1 2:2 3:5 4:3 5:2 6:2 
Roll counts for 8-sided die: 1:4 2:1 3:3 4:2 5:0 6:1 7:3 8:1 
Roll counts for 10-sided die: 1:2 2:2 3:2 4:1 5:0 6:2 7:1 8:1 9:1 10:3 
Sum counts: 3:0 4:0 5:0 6:0 7:0 8:2 9:3 10:1 11:0 12:4 13:0 14:0 15:1 16:0 17:0 18:1 19:1 20:1 21:1 22:0 23:0 24:0 
Average roll: 12.93

As another example, if the file yahtzee.txt contains the number 6 repeated 5 times (indicating 5 standard 6-sided dice), and that file is specified as the first command-line parameter and the number 10000 is the second command-line parameter, the following is a possible output:

Simulation has 5 fair dice:
  6-sided
  6-sided
  6-sided
  6-sided
  6-sided
Roll 1: 6 4 2 5 1 total: 18
Roll 2: 1 1 6 1 6 total: 15
Roll 3: 4 5 1 1 1 total: 12
... 9994 lines omitted ...
Roll 9998: 6 3 3 3 6 total: 21
Roll 9999: 1 1 1 6 5 total: 14
Roll 10000: 5 2 1 3 2 total: 13
Simulation summary:
Roll counts for 6-sided die: 1:1637 2:1674 3:1646 4:1694 5:1657 6:1692 
Roll counts for 6-sided die: 1:1656 2:1659 3:1634 4:1692 5:1677 6:1682 
Roll counts for 6-sided die: 1:1633 2:1674 3:1705 4:1723 5:1636 6:1629 
Roll counts for 6-sided die: 1:1698 2:1652 3:1708 4:1641 5:1625 6:1676 
Roll counts for 6-sided die: 1:1706 2:1659 3:1641 4:1715 5:1696 6:1583 
Sum counts: 5:2 6:5 7:19 8:33 9:84 10:134 11:242 12:421 13:535 14:715 15:868 16:953 17:995 18:1044 19:974 20:861 21:684 22:478 23:366 24:273 25:166 26:86 27:40 28:14 29:6 30:2 
Average roll: 17.49

Submitting

Your lab is "submitted" by having your BlueJ project in the approrpriate directory in your account. Your lab will be graded by a demonstration of your program for your lab instructor. The grade is based entirely on correctness, and is worth 100 lab points.