As you remember the first homework was dedicated to writing a program that simulates a coffee machine.
The first and the second task of this homework is also about Coffee Machine, but instead of using the procedure approach, you will use Object Oriented Programming.
The third task give you the opportunity to practice of using Java Collection Framework.
In this task, you will create the first version of the Coffee Machine which should make Espresso and Americano.
First of all, let's take a look at the class AbstractCoffeeMachine.
This class is abstract and has a few fields and methods.
Pay attention to the method makeCoffee(). You can use it to make an Espresso and Americano.
Create a public class CoffeeMachineV1 derived from AbstractCoffeeMachine
in the package com.softserveinc.task01.
After, you need to implement the abstract methods makeEspresso() and makeAmericano().
Both methods should invoke the method makeCoffee() defined in parent class AbstractCoffeeMachine.
The methods should return true if it is enough resources (water and coffee beans) to make a coffee, otherwise false.
The method makeEspresso() intended to simulate making the Espresso.
One cup of Espresso made on this coffee machine contains 30 ml of water and 22 g of coffee beans.
Method makeAmericano() intended to simulate making the Americano.
One cup of Americano made on this coffee machine contains 100 ml of water and 22 g of coffee beans.
Also, you need to create a constructor with three arguments (see for example how is implemented the constructor in the parent class). Important: you don't need to add a default constructor!
Run the unit test to check your solution.
The second version of the Coffee Machine should make Cappuccino and Latte.
You need to extend the first version of Coffee Machine to reuse existing code.
In the package com.softserveinc.task02 create the class CoffeeMachineV2 derived from the class CoffeeMachineV1.
Add the field milkReservoirCapacity (private final integer) to represent how much milk can be poured into the Coffee Machine.
Add the public constructor with four parameters (three like in the superclass and fourth's for milkReservoirCapacity).
Don't forget to invoke the constructor of the superclass.
Add the field milk (private integer) to represent how much milk now is present in the Coffee Machine.
Add the method addMilk() to pour milk in Coffee Machine (see for example how is implemented the method addWater()
and addCoffeeBeans() in the class AbstractCoffeeMachine).
Add the getter to the field milk.
Add the method makeCappuccino() intended to simulate making the Cappuccino.
To make Cappuccino it is needed to make Espresso and add 85 ml of milk.
Add the method makeLatte() intended to simulate making the Latte.
To make Latte it is needed to make Espresso and add 150 ml of milk.
Both methods makeCappuccino() and makeLatte() are returned boolean values that represent if it is possible to make
a coffee.
If it is not enough milk to make a coffee the methods should return false and print the message Not enough milk
by using System.err.println()
At the end run the unit test to check your solution.
Develop an app that allows for saving logins and passwords. The pair login-password corresponds to a certain user.
The main functionality of the program:
- Add a new user
- Delete a user
- Check if the user exists
- Change the password of a user.
You will use the existing class User.
To do it you should create the public class UserManager in package com.softserveinc.task03.
Add the private final field called users. It should have the type of Set<User>.
Initialize this field in the default constructor (use HashSet<> class).
Add the method register() with two parameters: login and password of String type.
The method should create the User and save it in the set users.
It returns nothing (void).
Add the method delete() with parameter login of String type.
The method should delete the User in the set users.
It returns nothing (void).
Add the method exists() with two parameters: login and password of String type.
The method should check if the User exists in the set users.
The method returns the boolean value.
If exists then returns true, otherwise - false.
Add the method changePassword() with three parameters: login, old password and, new password.
The method should find the User with the given login and old password in the set users and change the password to
the new password.
The method returns the boolean value.
If the User exists and the password is changed (successfully) then true, otherwise - false.
At the end run the unit test to check your solution.