Developing Java Applications with Spring and Spring Boot

Syntax

The syntax is different from Java syntax. At first glance, it can be a problem but after some hours of playing with Kotlin, it is not a problem at all.

There are two interesting reserved words to understand the usage and concepts:

• var: This is a variable declaration. It indicates the variable is mutable and can be reassigned, as developers need.

• val: This is a variable declaration which indicates the variable is immutable and cannot be reassigned anymore. This definition is like a final declaration in the Java language.

The variable declarations have a name, and after the desired data type, the colon is necessary in the middle as a separator. If the variable is initialized, the type is not necessary because the compiler can infer ...