Where to start learning Java?

Question

Java

So, I know all sorts of things:
php
python
perl
ruby
​​c

Most of the time I've been writing all sorts of backend things in ruby, as a result, at some point I ran into 30K rps limits.

Having thought a lot, I chose Java, advise all sorts of interesting documentation, screencasts and other goodies, so as not to spoil the immersion from the very beginning :)

Answer 1

From my own experience, I can say that you can learn a language only by starting to do something in it.
This should not be a very big task, and it is desirable that there is a person to whom you can ask questions, and not just google.
It's easier to learn Java by knowing C++. They are very similar in syntax (although the similarity ends there).
And yet - start with the Java SE platform (Standart Edition).
Start learning the technologies included in Java EE (Enterprise Edition) no earlier than after a year of active programming in Java SE, otherwise you risk getting a complete mess in your head.
From the literature I recommend:
1. Philosophy java (Thinking in Java), Bruce Eckel, 4th edition (to understand the principles of the language)
2. Herberdt Schildt, Java SE6 and Java2 - as desktop books
3. Java Code Conventions . This is a must to know. I didn't see it in Russian translation.

Answer 2

If you only need to optimize the application, it will be much cheaper to take it and architecturally optimize it than
1) decide to learn a _in_theory_ faster programming language and
2) completely rewrite everything in it without losing speed
Learning all the features of Java can take years, I have already all 4 years how tightly I work on it, and Java EE is still somewhat confused

Answer 3

if the problem is 30k rps, then you are solving it incorrectly. You need to learn Linux administration, not Java :)

Answer 4

What did you use to write in ruby ​​that you have 30k rps?
We take almost plain "HelloWorld" application and run ab -c 10 -n 1000
•rack 1200 rps
•sinatra 600 rps
•padrino 570 rps
•rails 140 rps
From books:
Cay S Horstmann Gary Sornell - Core Java - Volume I - Fundamentals
From The newest is the 2012 book.
Deitel PJ, Deitel HM - Java How to Program, 9th Edition
1500pp there, covers almost everything you need to get started, but it's better to skip any GUIs.

Answer 5

Probably, for a start it is worth studying the syntax of the language itself, not forgetting about all sorts of things like anonymous classes and Generics. It's fast, a few days to a week.
Then the standard library: collections, input-output (here it is listed what is there: en.wikipedia.org/wiki/Java_Platform , _Standard_Edition - but you don’t need to study all this). It's another week of intensive study.
This may already be enough for your tasks.
Then you can explore all sorts of JVM options for profiling and optimization.
If it's interesting, then you can look at servlets, Java Server Pages (or Faces? I forgot what the difference is), frameworks / libraries like Spring.

Answer 6

If you prefer to watch a couple of screencasts before reading, there is a course from lynda Java
Essential Training with David Gassner
www.lynda.com/Java-tutorials/Essential-Training/86005-2.html
.

Answer 7

There are good lectures on java: www.lektorium.tv/course/?id=22824 (or here rutracker.org/forum/viewtopic.php?t=3913055 )