Intermediate level will need about a dozen books and at least three years of real experience.
Bonita_Hermiston answered on April 4th 20 at 00:52
I would suggest youtube or Udemy and books after the video courses. Best book "JAVA. PROGRAMMING TECHNIQUES", I. N. Blinov, V. S. Affair. And foreign in my opinion for beginners it is better not to scroll, because it often happens that the localization is poor(if you know english that is another matter)
owen.OK answered on April 4th 20 at 00:54
Itself java you hardly need. We need more libraries and framework.
To determine where is the average level decide on subject area.
Ie define what you want to implement in Java and begin to learn the desired environment along with core java.
Well, the book is not enough, you need a lot of practice. Without this, read will quickly erode.