How do closures work in Java?

Question

Java

How to properly write the following code in Java (just an example):

int i = 0;
       List<String> listStr = Files.readAllLines(Paths.get("file.txt"));
       listStr.forEach((item) -> {
           i++;
       });

I get the error "Variable used in lambda should be effectively final".

Answer 1

You can get acquainted here , it is quite accessible in Russian.
In your specific case, AtomicInteger will help and increment it, or use an array.