method notations

.idea/dictionaries/Beppe.xml

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+<component name="ProjectDictionaryState">
+  <dictionary name="Beppe">
+    <words>
+      <w>beppe</w>
+    </words>
+  </dictionary>
+</component>

src/exercises/ooExcercises.scala

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+package exercises
+
+object ooExcercises extends App {
+
+
+
+
+  // novel and a writer class
+  // writer: first name, surname, year of birth
+  // =method full name
+  // novel: name, year of release, author
+  // -method authorAge (age at year of release), isWrittenBy(author), copy(new year of release) = new instance of Novel with new year of release
+
+  val au1 = new writer("beppe", "vanrolleghem", 1996)
+  val au2 = new writer("beppe2", "vanrolleghem2", 1997)
+  val nov1 = new novel("somebook",2004,au1)
+  println(nov1.isWrittenBy(au2))
+  println(au1.fullName())
+  println(nov1.authorAge())
+  val nov2 = nov1.copy(2020)
+  println(nov2.authorAge())
+
+
+
+  // counter class
+  // receives an int value
+  // method returns current count
+  //method to increment/decrement => new Counter
+  //overload inc/dec to receive an amount = new counter
+
+
+  var c = new counter(5)
+  println(c.currentCount())
+  c = c.increment()
+  c = c.increment()
+  println(c.currentCount())
+  println(c.decrement(3).currentCount())
+
+
+}
+
+
+
+
+
+class writer(firstName: String, surName: String, val yearOfBirth: Int) {
+  def fullName(): String = s"$firstName $surName"
+
+}
+
+class novel(name: String, yearOfRelease: Int, author: writer) {
+  def authorAge(): Int = yearOfRelease - author.yearOfBirth
+  def isWrittenBy(author: writer): Boolean = this.author == author
+  def copy (newYearOfRelease: Int): novel = new novel(name, newYearOfRelease, author)
+}
+
+
+
+class counter(i: Int) {
+  def currentCount(): Int = i
+  def increment(): counter = new counter(i+1)
+  def decrement(): counter = new counter(i-1)
+  def increment(in: Int): counter = new counter(i+in)
+  def decrement(de: Int): counter = new counter(i-de)
+}

src/lectures/part2oop/MethodNotations.scala

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+package lectures.part2oop
+
+object MethodNotations extends App {
+
+
+  class Person(val name: String, favoriteMovie: String) {
+    def likes(movie: String): Boolean = movie == favoriteMovie
+    def +(person: Person): String = s"${this.name} is hanging out with ${person.name}"
+    def unary_! : String = name.reverse
+    def isAlive: Boolean = true
+    def apply(): String = s"Hi, my name is $name and I like $favoriteMovie"
+
+
+  }
+
+
+  val mary = new Person("Mary", "Inception")
+  println(mary.likes("Inception"))
+  println(mary likes "Inception")
+  val tom = new Person("Tom", "Fight Club")
+  println(mary + tom)
+  println(mary.+(tom))
+
+  //this functionality is nice, but i will never use it because using a . is way more clear to me
+
+  println(1 + 2)
+  println(1.+(2))
+
+
+  // all operators are methods.
+  val x = -1
+  val y = 1.unary_-
+  println(x == y)
+
+  //unary only works with - + ~ !
+  //this on the other hand seems really usefull for certain things
+  println(!mary)
+
+  //println(mary isAlive) //postfix notation
+
+
+  //apply
+  println(mary.apply())
+  println(mary()) //so apply is kindof a default method
+
+
+}

src/lectures/part2oop/OOBasics.scala

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+package lectures.part2oop
+
+object OOBasics extends App {
+
+  val person = new Person("Beppe",23)
+  println(person.age)
+  println(person.x)
+  person.greet()
+  person.greet("Fred")
+
+}
+
+
+class NoFieldPerson(name: String, age: Int)
+
+// class parameters != fields
+
+class fieldPerson(name: String, val age: Int) //person.age not accessible, fieldPerson.age is accessible
+
+class Person(name: String, val age: Int) {
+  //body
+  val x = 2
+  println(1 + 3)
+
+  //this, fields etc...
+  def greet(name: String): Unit = println(s"${this.name} says: Hi, $name")
+
+
+  //overload
+  def greet(): Unit = println(s"Hi, I am $name")
+
+  //multiple constructors
+  //new constructor calls original constructor here
+  //means only usable for easyer default constructors, which can be easily fixed by using default parameters
+  def this(name: String) = this(name, 0)
+
+
+}