Try-with-resources and recent changes.

What is it?

Introduced in Java 7, it ensures that resources (like streams/connections) are closed automatically at the end of the block.

Requirement:

The resource must implement the AutoCloseable interface.

Java 9 Update:

You can use effectively final variables in the resource block:

BufferedReader reader = new BufferedReader(new FileReader("file.txt"));
try (reader) { // Valid in Java 9+
    System.out.println(reader.readLine());
}