task.md

In the previous sections, we have seen how case classes could be used to achieve information aggregation and also how classes could be used to achieve data abstraction or to define stateful objects.

What is the relationship between classes and case classes? How do they differ?

Creation and Manipulation

Remember the class definition of BankAccount:

  class BankAccount {

    private var balance = 0

    def deposit(amount: Int): Unit = {
      if (amount > 0) balance = balance + amount
    }

    def withdraw(amount: Int): Int =
      if (0 < amount && amount <= balance) {
        balance = balance - amount
        balance
      } else throw new Error("insufficient funds")
  }

And the case class definition of Note:

  case class Note(name: String, duration: String, octave: Int)

Let’s create some instances of BankAccount and Note and manipulate them.

Exercise

• Deposit 100 to the account.
• Create a C3 Note instance.