What you need to know to say “I know java core”?

Answer 1, Authority 100%

Well, in fact, the concept of Java Core is very blurry. Someone believes that this is all that is described in JLS, someone takes the basis of SCJP, someone some kind of own metrics. There are general people who call it Java Fundamentals, and the Core also includes OOP, work with collections and the foundations of multiplow. Here everything is very subjective here.
But I think, if you can answer all questions from this Interview , then it is quite confident Talk about knowing Java Core.

Answer 2, Authority 75%

As part of Bruce Eckel’s book “Java Philosophy”.

Answer 3

Then already 2 Timon Horstmann. It is also called java core

Answer 4

Probably to the answer to this issue, first of all, the Java syntax and means that distinguish this language from other OOP programming languages ​​are required. As mentioned earlier, it is most likely a manifestation of the OOP in Java, a collection, multithreading. In general, many books are written. And to accurately answer this question, few people can, you can take books that clamp Java and read the sections will become roughly understandable.