tim-from-marketing

Tim from Marketing

Welcome to Tim from Marketing on Exercism's Java Track. If you need help running the tests or submitting your code, check out HELP.md. If you get stuck on the exercise, check out HINTS.md, but try and solve it without using those first :)

Introduction

Nullability

In Java, the null literal is used to denote the absence of a value.

Primitive data types in Java all have a default value and therefore can never be null. By convention, they start with a lowercase letter e.g int.

Reference types contain the memory address of an object and can have a value of null. They generally start with an uppercase letter, e.g. String.

Attempting to assign a primitive variable a value of null will result in a compile time error as the variable always holds a primitive value of the type assigned.

//Throws compile time error stating the required type is int, but null was provided
int number = null;

Assigning a reference variable a null value will not result in a compile time error as reference variables are nullable.

//No error will occur as the String variable str is nullable
String str = null;

Instructions

In this exercise you'll be writing code to print name badges for factory employees.

1. Print a badge for an employee

Employees have an ID, name and department name. Employee badge labels are formatted as follows: "[id] - name - DEPARTMENT". Implement the Badge.print() method to return an employee's badge label:

Badge badge = new Badge();
badge.print(734, "Ernest Johnny Payne", "Strategic Communication");
// => "[734] - Ernest Johnny Payne - STRATEGIC COMMUNICATION"

Note that the department should be uppercased on the label.

2. Print a badge for a new employee

Due to a quirk in the computer system, new employees occasionally don't yet have an ID when they start working at the factory. As badges are required, they will receive a temporary badge without the ID prefix. Modify the Badge.print() method to support new employees that don't yet have an ID:

Badge badge = new Badge();
Badge.print(null, "Jane Johnson", "Procurement");
// => "Jane Johnson - PROCUREMENT"

3. Print a badge for the owner

Even the factory's owner has to wear a badge at all times. However, an owner does not have a department. In this case, the label should print "OWNER" instead of the department name. Modify the Badge.print() method to print a label for the owner:

Badge badge = new Badge();
badge.print(254, "Charlotte Hale", null);
// => "[254] - Charlotte Hale - OWNER"

Note that it is possible for the owner to also be a new employee:

Badge badge = new Badge();
badge.print(null, "Charlotte Hale", null);
// => "Charlotte Hale - OWNER"

Source

Created by

• @smcg468