Variables in Kotlin, differences with Java: 'var' vs. 'val'?

Question

I am trying to learn Kotlin. What is val, var and internal in Kotlin compared to Java?

In Java:

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Answer 1

val : immutable data variable

var : mutable data variable

When you converted your Java code to Kotlin:

1. A converter found that you have not initialised variables, so it made them var(mutable) as you will initialise them later.

2. Probably your variables are unused, so the converter made them internal, guessing you will not use them outside of your package.

For more information on var and var read this, and for internal read this.