Description
The first programming project involves writing a program that computes the minimum, the
maximum and the average weight of a collection of weights represented in pounds and ounces
that are read from an input file. This program consists of two classes. The first class is the
Weight class, which is specified in integer pounds and ounces stored as a double precision
floating point number. It should have five public methods and two private methods:
1. A public constructor that allows the pounds and ounces to be initialized to the values
supplied as parameters.
2. A public instance method named lessThan that accepts one weight as a parameter and
returns whether the weight object on which it is invoked is less than the weight supplied
as a parameter.
3. A public instance method named addTo that accepts one weight as a parameter and adds
the weight supplied as a parameter to the weight object on which it is invoked. It should
normalize the result.
4. A public instance method named divide that accepts an integer divisor as a parameter. It
should divide the weight object on which the method is invoked by the supplied divisor
and normalize the result.
5. A public instance toString method that returns a string that looks as follows: x lbs y oz,
where x is the number of pounds and y the number of ounces. The number of ounces
should be displayed with three places to the right of the decimal.
6. A private instance method toOunces that returns the total number of ounces in the weight
object on which is was invoked.
7. A private instance method normalize that normalizes the weight on which it was
invoked by ensuring that the number of ounces is less than the number of ounces in a
pound.
Both instance variable must be private. In addition the class should contain a private named
constant that defines the number of ounces in a pound, which is 16. The must not contain any
other public methods.
The second class should be named Project1. It should consist of the following four class (static)
methods.
1. The main method that reads in the file of weights and stores them in an array of type
Weight. It should then display the smallest, largest and average weight by calling the
remaining three methods. The user should be able to select the input file from the default
directory by using the JFileChooser class. The input file should contain one weight per
line. If the number of weights in the file exceeds 25, an error message should be
displayed and the program should terminate.
2. A private class method named findMinimum that accepts the array of weights as a
parameter together with the number of valid weights it contains. It should return the
smallest weight in that array.
3. A private class method named findMaximum that accepts the array of weights as a
parameter together with the number of valid weights it contains. It should return the
largest weight in that array.
4. A private class method named findAverage that accepts the array of weights as a
parameter together with the number of valid weights it contains. It should return the
average of all the weights in that array.
Be sure to follow good programming style, which means making all instance variables private,
naming all constants and avoiding the duplication of code. Furthermore you must select enough
different input files to completely test the program.
Grading Rubric:
The following grading rubric will be used to determine your grade:
Attribute Meets
Weight class 40 points
It should have five public methods and two private methods:
1. A public constructor that allows the pounds and ounces
to be initialized to the values supplied as parameters.
2. A public instance method named lessThan that accepts
one weight as a parameter and returns whether the weight
object on which it is invoked is less than the weight supplied
as a parameter.
3. A public instance method named addTo that accepts one
weight as a parameter and adds the weight supplied as a
parameter to the weight object on which it is invoked. It
should normalize the result.
4. A public instance method named divide that accepts an
integer divisor as a parameter. It should divide the weight
object on which the method is invoked by the supplied
divisor and normalize the result.
5. A public instance toString method that returns a string
that looks as follows: x lbs y oz, where x is the number of
pounds and y the number of ounces. The number of ounces
should be displayed with three places to the right of the
decimal.
6. A private instance method toOunces that returns the total
number of ounces in the weight object on which is was
invoked.
7. A private instance method normalize that normalizes the
weight on which it was invoked by ensuring that the number
of ounces is less than the number of ounces in a pound.
Both instance variable must be private. In addition the class
should contain a private named constant that defines the
number of ounces in a pound, which is 16. The must not
contain any other public methods.
Project1 class 40 points
It should consist of the following four class (static) methods.
1. The main method that reads in the file of weights and
stores them in an array of type Weight. It should then
display the smallest, largest and average weight by calling
the remaining three methods. The user should be able to
select the input file from the default directory by using the
JFileChooser class. The input file should contain one weight
per line. If the number of weights in the file exceeds 25, an
error message should be displayed and the program should
terminate.
2. A private class method named findMinimum that accepts
the array of weights as a parameter together with the number
of valid weights it contains. It should return the smallest
weight in that array.
3. A private class method named findMaximum that accepts
the array of weights as a parameter together with the number
of valid weights it contains. It should return the largest
weight in that array.
4. A private class method named findAverage that accepts
the array of weights as a parameter together with the number
of valid weights it contains. It should return the average of
all the weights in that array.
Test Cases 10 points
Test cases are supplied in the form of table with columns
indicating the input values, expected output, actual output
and if the test case passed or failed.
Select at least 3 different input files to completely test the
program.
Test cases were included in the supporting word or PDF
documentation.
Documentation and Style
guide
10 points
Screen captures were provided and labeled for compiling
your code, and running each of your test cases.
Header comments include filename, author, date and brief
purpose of the program.
In-line comments used to describe major functionality of the
code.
Meaningful variable names and prompts applied.
Class names are written in UpperCamelCase.
Variable names are written in lowerCamelCase.
Constant names are in written in All Capitals.
Braces use K&R style.
Declare all instance variables private.
Avoids the duplication of code.
