Marantle/nutcracker

Nutcracker

A little personal project for parsing monthly salaries from a csv file and exposing them on a simple website.

The data is read from \src\main\resources\hourlist.csv and the test data is read from \src\test\resources\testhours.csv.

Implemented using Spring Boot Web framework for backend and Thymeleaf as the templating engine for frontend. The front end is a simple website composed mostly of simple tables that expose the data, using Bootstrap.

As this handles currencies, I've used BigDecimal's to keep the currencies as accurate as possible, could also propabbly have used integer/long to represent cents.

Currency calculations

Logic is that overtime compensation increases every 2 hours, all though this can be changed. A work day is 8 hours long and after that overtime kicks in, irregardless if the 8 hours contains evening hours. Overtime goes through 1.25, 1.5, 2 multipliers to regular salary. Evening compensation is $1.15. Regular salary is $3.75. Overtime and evening compensations do not stack.

The following variables are stored in MyUtilities.java all though they could easily be externalized to a settings file. You can modify any of these to affect the application logic.

public static final double REGULAR_WAGE = 3.75;
public static final double EVENING_COMPENSATION = 1.15;
public static final int OVERTIME_INCREMENT = 2;
public static final double[] OVERTIME_COMPENSATIONS = {1.25, 1.5, 2};

Rounding values

As for rounding the results, up until the values are requested to be displayed at any point, no rounding takes place. This is different from when if the rounding took place whenever any value was updated, it would most likely cause only a few cents difference, as these test results demonstrate.

No rounding until displayed, after which half up.
1 Janet Java    2014/03 $690,68 
2 Scott Scala   2014/03 $651,30 
3 Larry Lolcode 2014/03 $377,00

Rounding to ceiling any time these values were added to.
1 Janet Java    2014/03 $690,77 
2 Scott Scala   2014/03 $651,37 
3 Larry Lolcode 2014/03 $377,07

Rounding to half up any time these values were added to.
1 Janet Java    2014/03 $690,69 
2 Scott Scala   2014/03 $651,31 
3 Larry Lolcode 2014/03 $377,01

Rounding to half even, aka banker's rounding, any time these values were added to.
1 Janet Java    2014/03 $690,66 
2 Scott Scala   2014/03 $651,30 
3 Larry Lolcode 2014/03 $377,00

Additional libraries used

Dependencies are handled by gradle.

jackson-datatype-jsr310 Datatype module to make Jackson (http://jackson.codehaus.org) recognize Java 8 Date & Time API data types (JSR-310). Enabled jackson to convert Java 8 Date & Time to json
apache commons-io for easier file handling
webjars for bootstrap and jquery

Running

You can build or run the web application with the following commands in the projects root directory

gradlew build
gradlew bootrun

Or by running NutcrackerApplication.java from your favorite ide.

after which you can find the application running at http://localhost:8080/

Paths

/workshifts Displays daily Workshifts for each person
/persons Displays all persons
/workdays Displays daily work hours for each person
/salaries Displays daily salaries for each person
/salaries/monthly Displays monthly salaries for each person

Each path also has sub path of /raw that just dumps the json data to your browser.

Tests

There are some tests for checking that the data got parsed and calculated correctly and these tests use their own csv file located in \src\test\resources\testhours.csv. Run these tests with below command, there should be no output if they succeed currently.

gradlew test

Or if possible, directly run \src\test\java\com\marantle\nutcracker\TestRunner.java for the same tests. These tests use the included testhours.csv by comparing the parsed data to handmade calculations for multiple persons.

There is also \src\test\java\com\marantle\nutcracker\RunSimpleTest.java which just outputs the monthly wages to console

Also included is a data comparisons.xlsx for checking the data with manual calculations compared to the output got from the application.

Packages

/bootstrap Intializes the data when running the web application
/configuration Generic spring configuration
/controller Web controllers
/model WorkDay, Salary, WorkShift and Person java classes
/parser The parser that maps the csv data to the respective models
/repository The DataHolder that has as static sets, list of all the parsed data and NutRepo that is used to access this data from elsewhere in the app
/util Contains time formats, value converts and other utilitary methods and fields used in multiple places

Marantle / nutcracker