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|
Learning Profile for Assignment #1, And Question #2
Name: Mo Khan
Student ID: 3431709
1. Problem Statement:
Modify the following program to the specifications given below:
* I. Add a new status `SingleParent` where the tax is computed as a SINGLE but with a further reduction of $5000 per child.
* II. Add a new tax condition - if the income is greater than $249,999 for SINGLE, then add a tax of 25% on income amount above $150,000; if the income is greater than $349,999 for MARRIED, then add a tax of 35% on income amount above $200,000.
* III. Unknown status - if the status doesn't belong to `SINGLE` or `MARRIED` or `SINGLE_PARENT`, then compute a 33% tax on the income.
```java
import java.util.Scanner;
public class TaxReturn {
public TaxReturn(double anIncome, int aStatus) {
income = anIncome;
status = aStatus;
}
public double getTax() {
double tax = 0;
if (status == SINGLE) {
if (income <= SINGLE_BRACKET1) tax = RATE1 * income;
else if (income <= SINGLE_BRACKET2)
tax = RATE1 * SINGLE_BRACKET1 + RATE2 * (income - SINGLE_BRACKET1);
else
tax =
RATE1 * SINGLE_BRACKET1
+ RATE2 * (SINGLE_BRACKET2 - SINGLE_BRACKET1)
+ RATE3 * (income - SINGLE_BRACKET2);
} else {
if (income <= MARRIED_BRACKET1) tax = RATE1 * income;
else if (income <= MARRIED_BRACKET2)
tax = RATE1 * MARRIED_BRACKET1 + RATE2 * (income - MARRIED_BRACKET1);
else
tax =
RATE1 * MARRIED_BRACKET1
+ RATE2 * (MARRIED_BRACKET2 - MARRIED_BRACKET1)
+ RATE3 * (income - MARRIED_BRACKET2);
}
return tax;
}
public static final int SINGLE = 1;
public static final int MARRIED = 2;
private static final double RATE1 = 0.15;
private static final double RATE2 = 0.28;
private static final double RATE3 = 0.31;
private static final double SINGLE_BRACKET1 = 21450;
private static final double SINGLE_BRACKET2 = 51900;
private static final double MARRIED_BRACKET1 = 35800;
private static final double MARRIED_BRACKET2 = 86500;
private double income;
private int status;
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
System.out.print("Please enter your income: ");
double income = in.nextDouble();
System.out.print("Enter S (single) or M (married): ");
String input = in.next();
int status = 0;
if (input.equalsIgnoreCase("S")) status = TaxReturn.SINGLE;
else if (input.equalsIgnoreCase("M")) status = TaxReturn.MARRIED;
else {
System.out.println("Bad input.");
return;
}
TaxReturn aTaxReturn = new TaxReturn(income, status);
System.out.println("The tax is " + aTaxReturn.getTax());
}
}
```
2. Description of the Code:
I started by adding tests for the existing code. By adding test coverage
for the existing code, this makes it possible to add new features
without breaking old features.
I chose to decrease the taxable income in the constructor if the person
is single.
3. Errors and Warnings:
```bash
モ mvn test
[INFO] Scanning for projects...
[INFO]
[INFO] -------------------< ca.mokhan.comp268:assignment1 >--------------------
[INFO] Building assignment1 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- fmt-maven-plugin:2.8:format (default) @ assignment1 ---
[INFO] Processed 48 files (0 reformatted).
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ assignment1 ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory /Users/mokha/development/gh/comp-268/src/main/resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ assignment1 ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 24 source files to /Users/mokha/development/gh/comp-268/target/classes
[INFO]
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ assignment1 ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory /Users/mokha/development/gh/comp-268/src/test/resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) @ assignment1 ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 24 source files to /Users/mokha/development/gh/comp-268/target/test-classes
[INFO]
[INFO] --- maven-surefire-plugin:2.12.4:test (default-test) @ assignment1 ---
[INFO] Surefire report directory: /Users/mokha/development/gh/comp-268/target/surefire-reports
-------------------------------------------------------
T E S T S
-------------------------------------------------------
Running ca.mokhan.comp268.AppTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.007 sec
Running ca.mokhan.test.CandidateTest
Tests run: 4, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.053 sec
Running ca.mokhan.test.NumberTest
Tests run: 5, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.021 sec
Running ca.mokhan.test.EmployeeSavingsTest
Tests run: 6, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.008 sec
Running ca.mokhan.test.CartesianCoordinateSystemTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0 sec
Running ca.mokhan.test.CommunicationTest
Tests run: 2, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0 sec
Running ca.mokhan.test.TaxReturnTest
Tests run: 12, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.001 sec
Running ca.mokhan.test.BanffMarathonRunnerTest
Tests run: 4, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.001 sec
Running ca.mokhan.test.AddressBookTest
Tests run: 12, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0 sec
Running ca.mokhan.test.TriangleTest
Tests run: 2, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0 sec
Running ca.mokhan.test.BonusOnSavingsTest
Tests run: 2, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0 sec
Running ca.mokhan.test.HailstoneSequenceTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0 sec
Results :
Tests run: 52, Failures: 0, Errors: 0, Skipped: 0
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.871 s
[INFO] Finished at: 2019-05-13T20:07:42-06:00
[INFO] ------------------------------------------------------------------------
```
4. Sample Input and Output:
Test cases are defined in `TaxReturnTest.java`.
5. Discussion:
There is a lot of conditional logic in `getTax()`. I considered
[Refactor conditional with polymorphism](https://refactoring.com/catalog/replaceConditionalWithPolymorphism.html)
but decided not to make this change.
|
