A DESCRIPTION OF THE PROBLEM :
The statement within lambda "System.out.println("x = " + x);" does not try to access the FirstLevel.x variable, but rather the parameter of the methodInFirstLevel.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
where the lambda expression myConsumer tries to access the methodInFirstLevel parameter:

System.out.println("x = " + x);
ACTUAL -
where the lambda expression myConsumer tries to access the FirstLevel.x variable:

System.out.println("x = " + x);

URL OF FAULTY DOCUMENTATION :
https://docs.oracle.com/javase/tutorial/java/javaOO/lambdaexpressions.html