Difference Between Traits and Abstract Classes in Scala
Last Updated :
13 Feb, 2019
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In Scala, an abstract class is constructed using the abstract keyword. It contains both abstract and non-abstract methods and cannot support multiple inheritances.
Example:
// Scala program to illustrate how to // create an abstract class // Abstract class abstract class Abstclass { // Abstract and non-abstract method def portal def tutorial() { println("Scala tutorial") } } // GFG class extends abstract class class GFG extends Abstclass { def portal() { println("Welcome!! GeeksforGeeks") } } object Main { // Main method def main(args: Array[String]) { // object of GFG class var obj = new GFG (); obj.tutorial() obj.portal() } } |
Output:
Scala tutorial Welcome!! GeeksforGeeks
Like a class, Traits can have methods(both abstract and non-abstract), and fields as its members. Traits are just like interfaces in Java. But they are more powerful than the interface in Java because in the traits we are allowed to implement the members.
Example:
// Scala program to illustrate how to // create traits // traits trait mytrait { // Abstract and non-abstract method def portal def tutorial() { println("Scala tutorial") } } // GFG class extends trait class GFG extends mytrait { def portal() { println("Welcome!! GeeksforGeeks") } } object Main { // Main method def main(args: Array[String]) { // object of GFG class var obj = new GFG (); obj.tutorial() obj.portal() } } |
Output:
Scala tutorial Welcome!! GeeksforGeeks
| Traits | Abstract Class |
|---|---|
| Traits support multiple inheritance. | Abstract class does not support multiple inheritance. |
| We are allowed to add a trait to an object instance. | We are not allowed to add an abstract class to an object instance. |
| Traits does not contain constructor parameters. | Abstract class contain constructor parameters. |
| Traits are completely interoperable only when they do not contain any implementation code. | Abstract class are completely interoperable with Java code. |
| Traits are stackable. So, super calls are dynamically bound. | Abstract class is not stackable. So, super calls are statically bound. |
