Scala Case Classes - Are They Just Structures?

Question

So, I just found out about scala class classes, and they tell me that they are used to provide a simple wrapper around a lot of properties, to make it easier to check for equality. But now I have two questions:

• Is it the same as structure in C ++ / C #?
• Are class classes a value type or a reference type?

Answer 1

Firstly, a structin C ++ and structin C # are two different things. So the assignment of case classes in scala coincides with those that 2 things do not make sense.

• ++ - , . . .

• # . , . Java. ++, class struct.

, , # ( ), Java/# ( ). . , .

, - JVM. , , . - , case , #. JVM , GC ( ).

, :

.

.

Answer 2

. scala case ... scala.

scala , , .copy .apply .unapply -. .toString , .equals, , ref.

scala.

Answer 3

Scala Java. .

Scala case scala, :

• ( case , public final Java, case var)
• equals hashCode,
• Method applyand unapplycompanion object
• A toStringmethod showing all constructor values
• A copymethod

Here is an example:

case class MasterOfTheUniverse(name: String, power: Int)

scala> MasterOfTheUniverse("He-Man", 100).name
res1: String = He-Man

scala> MasterOfTheUniverse("He-Man", 100).power
res2: Int = 100

scala> MasterOfTheUniverse("He-Man", 100).toString
res3: String = MasterOfTheUniverse(He-Man,100)

scala> MasterOfTheUniverse("He-Man", 100) == MasterOfTheUniverse("She-Ra", 90)
res4: Boolean = false

scala> MasterOfTheUniverse("She-Ra", 90) == MasterOfTheUniverse("She-Ra", 90)
res6: Boolean = true

scala> MasterOfTheUniverse("He-Man", 100).copy(name = "He-Manatee")
res7: MasterOfTheUniverse = MasterOfTheUniverse(He-Manatee,100)