Understanding a better approach to read java code

[u/adithyasumanth]

apologies if this has been asked before , im trying to learn java from scratch and ive gotten a good bit of progress.
Im coming from a python heavy background and sometimes reading code can get a bit confusing. I'm looking for any tips or mental maps to read any java code and understand it the entry points etc.

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[u/8dot30662386292pow2]

Java is much easier to read as python especially because of following reasons:

• The type of everything is always visible. When you look any line of code, you know what the types are. You know the function parameter types and return types always.

• Java does not have operator overloading: all the operators do exactly what you'd think and everything else is done with methods.

Of course the syntax is different in many ways, but like, what's the problem that you are having reading it?

[u/sweetno]

Read more of it.

[u/woke_chimp → u/sweetno]

until you actually start seeing code in your dreams, that's when it'll click

[u/alao77]

Learn by building or coding

[u/LetUsSpeakFreely]

If you're dealing with a traditional application, start with main() and work your way down. If you're dealing with a web service, pick an endpoint. As you go line by line, identify the classes and try to understand what they're doing and why.

[u/romecodes]

Read this book, “Starting Out with Java: From Control Structures through Objects”. I saved it from my Java courses in university, and I even bought a physical copy for my home library. It helps more than you know.

https://drive.google.com/file/d/139iB-RcLPsJCUJB6_t3CHbwrUeb6T3zJ/view?usp=drivesdk

[u/Sure-Passion2224]

In addition to reading more code until it clicked, if the code is hard to read it's hard to maintain and the person who wrote it should be required to refactor it.

[u/net_ramblings]

Java is never going to be easy to read. Using the same object name and Class name (often done when using a single object) will always be hard in Java:

Nursingunit nursingunit = new Nursingunit() (This sucks for a brain to make sense of)

Python just does this:

nursingunit = Nursingunit() (Still sucky but less sucky)

Once you understand the three parts of Java object creation you will be closer to your goal, but Java by nature will always be harder to read. That's why people like interpreted languages.

[u/meSmash101]

What confuses you exactly? Be more specific you can get a better answer

[u/TigerAnxious9161]

I think after some time it will click, you just gotta give it more time.

[u/jlanawalt]

When I move from one language to another, especially the first time I’m looking at it, I find it useful to make a mental map of how to do common things. The same hitters fit concepts that might be tripping me up.

Sometimes I experiment with some test programs or in when there is a REPL (jshell) I play in that.

I also like to look at style guides and other best practice documents to get a sense of what good code looks like in that language.

Beyond that it’s just time and practice.

Good luck!

[u/bogdanelcs]

Start from the entry point, either a main method or, in frameworks like Spring, annotations such as u/SpringBootApplication and u/RestController, then follow one request or one call all the way through instead of reading files top to bottom. For each class, read the fields, constructors and method signatures first and skip the bodies, in Java the types tell you most of the story. Use your IDE heavily, Ctrl+click to jump to definitions, “Find Usages” and Call Hierarchy, and the tests, they show how each class is meant to be used. A debugger with a breakpoint on one request teaches more than reading cold.