Scala and Spark for Big Data Analytics

Variable initialization

In Scala, it's a good practice to initialize the variables once declared. However, it is to be noted that uninitialized variables aren't necessarily nulls (consider types like Int, Long, Double, Char, and so on), and initialized variables aren't necessarily non-null (for example, val s: String = null). The actual reasons are that:

• In Scala, types are inferred from the assigned value. This means that a value must be assigned for the compiler to infer the type (how should the compiler consider this code: val a? Since a value isn't given, the compiler can't infer the type since it can't infer the type, it wouldn't know how to initialize it).
• In Scala, most of the time, you'll use val. Since these are immutable, you wouldn't ...