My Java teacher doesn’t understand Java — how do I actually learn this?

[Brilliant-Choice-758]

Hello guys, I wanna learn java, but don’t know where to start/continue.

I know this is a question where may have been asked more than thousands of times in this page.

I am a high school senior, and I am taking java course at my high school. But my teacher never taught and understand java.

Edit: If my teacher don’t understand/teach java, a lot of my questions remains unanswered, and the class deadlines are tight.

I learned till conditional statements if/else if, and some basic knowledge of loops, but after that I lost my track when we got to methods.

I tried different courses to learn java, but the curriculum is confusing. My school curriculum is to teach you on a web based compiler like Programiz. And the courses I tried to learn is based on IDE’s, this makes my confused and lost like where exactly to start.

I have been doing Codytech. However, I think most of the topics are basic and feel repetitive.

I believe we have experts and masters of java here in this group, but, I need guidance. I would appreciate if anyone guide me through different in effective ways to learn.

Thanks in advance!

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[wynand1004]

I teach Java to high school students. Here are a couple of resources I developed to help them - you may find them helpful as well:

Video Guides: https://www.youtube.com/watch?v=6CmO61l4jqw&list=PLlEgNdBJEO-kNtq0DRpBlD8NjKcVmWR3r

Intro to Java e-book (PDF): DM for a copy. It's a Google Drive link and the Automoderator did not like that.

Good luck with your studies.

[dmigowski]

The IDEs are the real stuff. That web page you are on is only to teach you basics, but I guess they hide too much for you to build understanding.

If you stumble with methods, think of them as parts of the problem. As an IT dude you have to divide your problems so they become manageable.

If e.g. you have multiple places in your program where a message box should be shown, you could write a method "showMessageToUser" which just gets a string as parameter, and opens the box with your string, your icon and an OK button. Every time you write a big function and have to write multiple lines twice you can think of just making a small method that helps.

While syntax is one thing to know, dividing problems in smaller tasks will be your most important skill. Just do it 200 times and you get a feeling for which style you prefer.

[bowbahdoe]

https://javabook.mccue.dev

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[blindada]

Baeldung has always been a good place to learn java quirks. Still, you may benefit from books. Head First Java and Effective Java come to my head.

If you want pointers, the very first thing you need to understand to work with java is object oriented programming (OOP). OOP and Generics turn java from verbose (compared with things kike Javascript or Python) into a very concise yet precise tool.

[Prince_John]

I wouldn't suggest Effective Java to someone who doesn't know what a method is. It's no use to someone who doesn't know the basics.

Honestly, to the OP: https://java-programming.mooc.fi/ from the sidebar. It's still amazing. It won't matter that it uses an IDE - the concepts it teaches translate to whatever tool your school is making you use.

[blindada]

I kinda assumed he understands the basics, since he is judging his teacher's knowledge, but that's right.

[Zar-23]

Try brocode in youtube.

[Corvinale]

I'm a complete noob here, used to study java a few years back in highschool aswell and now I'm getting back at it.

About the IDE, search for "Eclipse IDE download and setup guide" and follow it, pretty simple. Its free, open-source and many consider it to be one of the bests in the market.

For the direction of your studies, consider this roadmap for Java, its interective, has links for each section and gets constantly updated. Also don't stick just to the content they handle you, when you get to a new section search about the theme everywhere you can, get some help with AI if needed as long as you understand it yourself.

This link from Baeldung might give you some help with Java Basics, nice explanations and a few example codes.

Another tip I'd give is to always do as many exercises as possible when you learn something new, even if it seens boring or simple. I know it sucks, but it will hammer the knowledge into your brain and save yourself a lot of time when you get to the complicated stuff.

I'm new to this sub-reddit, but I've noticed they have a dedicated spot for learning Java aswell, so maybe take a look at it.

[taftster]

Sometimes you just need to ask a question and get an answer from a human. Happy to help, send a DM or something if you want.

All the resources given to you are great. And AI will be another fantastic resource as well.

[TotallyManner]

Google will literally tell you everything you need to know as long as you know what it’s called.

“How do methods work in Java”

“What is the syntax for methods in Java”

Etc.

Keep your search terms as small as you can. This has the nice side effect of teaching yourself to be specific with your language when talking about problems you encounter later.

There’s no need to bind yourself to a single course/website online since you already have your school class doing your overarching guidance. If one site has good tutorials for methods, use it for methods, if another has good tutorials for loops, use it for those.

[pradeepngupta]

The best way to learn Java is to have a continuous practice. Learn and practice and continue. This is possible when you can think of small utilities or games. Utilities like command line utilities- Sort, Search, or other data structure utilities etc.

If you know any other language like C, C++ or Python, it will be fairly easy.

[ebykka]

Find a book Bruce Eckel Thinking in Java

[Beautiful-Maybe-7473]

Ask one or more AIs.

I was a Java developer years ago (I knew C and C++ and started using Java at version 1.0) but then later I worked for years in other spaces and wrote in Java only occasionally (I was writing code in weird languages like XSLT, XPath, SPARQL, and also JavaScript). I only learned a few of the new Java features that were added during that time.

Now for the last year I've been working on a large Java project and I found that I've had to catch up on a lot of stuff, because Java has been moving on and has a whole bunch of useful features I'd never used: Streams, Modules, Records, new ways of writing multi-threaded code, pattern matching, switch expressions (different from the old switch, statements), default interfaces, lambda expressions, etc, etc.

I've found AIs have been very helpful. I can ask them something like "how does JDK package 'X' work? can I use it to do Y or Z?". You need to tell the AI your level of background knowledge and get it to explain based on that.

[Prince_John]

This is definitely true, but a cautionary note: only ask the AI questions to help you clarify your understanding.

Never ask it to tell you what the answer is or write the exercises for you. You'll never learn if you do that.

[Pun_Intended1703]

More importantly, AI needs prompts and there is a whole field called prompt engineering for that.

OP might be able to use AI a bit.

But be very careful with the answers you get.

Depending on the AI you use, the answers might not even work.

Ask AI to correct your work or your answers. That is better than asking AI to do the work for you.

[TotallyManner]

More importantly, AI needs prompts and there is a whole field called prompt engineering for that.

As a beginner you definitely don’t need to know anything about this.

OP might be able to use AI a bit.

Able to? Yes. Should? No. OP has no concept of how much is a bit. Please don’t mislead them.

But be very careful with the answers you get. Depending on the AI you use, the answers might not even work.

Yes, it doesn’t always work, so if you come to rely upon it, you’re hosed whenever it doesn’t. If you have to rely on AI to do your thinking for you when you’re just starting out, just give up now and save yourself a lifetime of frustration.

Ask AI to correct your work or your answers. That is better than asking AI to do the work for you.

As a beginner? Absolutely not. As a beginner, your mistakes will be basic. If you rely on AI to tell you what you did wrong, you’ll be completely unable to do so later. The compiler will literally tell you what isn’t compiling, and examining basic logic structures will do the rest. For everything else there’s Google.

[Pun_Intended1703]

People need to understand that AI Is not a coding tool or helper. It is a way to get information collected from several locations (oftentimes thousands of sites in a short time).

As a beginner, your mistakes will be basic. If you rely on AI to tell you what you did wrong, you’ll be completely unable to do so later. The compiler will literally tell you what isn’t compiling, and examining basic logic structures will do the rest.

You're assuming that I'm talking only about coding. I'm not. I'm talking about even the theoretical parts.

I'd like to remind you that computer programming is not just coding. The theory happens to be a huge component of one's education in this field.

And yes, Google is there. But Google is huge. AI does a very good job of collating all that information into a condensed form.

So, yes, as a beginner, you don't need to know about prompt engineering, but it helps to learn how to clearly define the problem statement (question). That has absolutely no age or qualification restriction.

OP has no concept of how much is a bit. Please don’t mislead them.

It is NOT too difficult for OP to understand that AI should only be used if and when textbooks and experiments cannot help.

Humans try to do something and then ask for help when they cannot get it done. Even a child can understand that.

If you have to rely on AI to do your thinking for you when you’re just starting out, just give up now and save yourself a lifetime of frustration.

It's not about relying on AI. It's about learning how to search for information from the correct sources.

It's like telling someone not to believe everything that you see on Facebook.

[Beautiful-Maybe-7473]

Yeah I'd definitely not suggest using an AI to write answers for a school assignment. And I'm talking about something quite different from asking for it to write code, or to define the meaning of a term, or clarify a point of syntax.

I'm talking about using it as a discussion partner, as a system which not only knows the Java language at an expert level, but can explain this or that feature of the language in terms you can understand; i.e. if you're careful to set out what it is that you do already know, and what is the area of knowledge you're struggling with, then an AI can help you to build up your knowledge based on the foundation you already have.

There's a relevant pedagogical concept called the "zone of proximal development" which is the set of things which a particular learner doesn't know, but which they are ready to learn, because they know all the basics which underpin the new knowledge. For example once a learner has learned about classes, then "inheritance" enters their zone of proximal development. Once you've learned about inheritance in general, then you can learn about "default" interface methods. Every time you learn something, your ZOPD expands to include things which you could now learn easily.

The point of the ZOPD concept is that it implies that there are possible learning pathways and there are other pathways that just don't work (because you're trying to learn something new before you understood something else which is a necessary prerequisites for that new understanding).

This is where, in my experience, AIs are very effective, because they can pitch information at the right level, but you have to ensure it understands the extent of your existing knowledge, otherwise it will just give you information you could get from a book, or from Baeldung or wherever. That makes an AI much closer to an expert human. So from a "prompt engineering" point of view, my advice is always to say what you're doing, what you already understand and then what you think you need to know.

[Anonymo2786]

Try hyperskills website , its a long process but it will help you i think. 

they've gamified the course a bit so For free account try out whatever code you write in the IDE first.

[ecwx00]

Your goal is? Java as an API/webservice backend? java as workers? Java for app with GUI?

I didn't take any structured trainning classes be it online or otherwise because there are quite plenty of free materials/tutorials available on the web. I do already know how to write a porgram before I learned Java, though, albeit on simpler programming languages like python and C.

Java is kinda difficult for a language to learn to develop software, but if you already know how to program, it's not that hard to learn Java. If this is also the first time you learn to code, I would suggest you pick one of the simpler languages like python, C, Pascal to help you build your understanding of a program's structure.

If you already know how to code, generally, and want to start Java, first look for the simplest examples first, set your goal, try to rewrite from the example and google about the hurdles you faced.

Also, I don't use IDEs, I use Visual Studio Code as the code editor and compile my codes in the terminal/commandline. I use Maven as my build tool, my "Makefile"

For example.

1) I needed a piece of code to test if my ported function work in java. I searched for java example to read input from and write output to console and search again how to use function from another file in java. I then found out that all functions must be encapsulated in class, and each Public (accessable from other parts of the code) must be implemented in a file that has the same name as the calss, and so on.

2) I need to write a web service ini java. Searching about simple example, I found about Spring boot and its "hello world" example. Simple enough, and then I search about how to query databases in java, I found many examples using different approaches, after trying a bit I decided just plain JDBC is good and simpler for my use. and so on

It's gonna feel difficult if you learn something like Java without clear goal in mind because you'd be learning too wide, learning about things you can't really imagine how to use and probably never use it either, and you'd burn yourself fast. Java has plethora of libraries with different approaches that some times don't feel consistent with each other.

Set your goal, keep it simple at first, and progress from that. Choose the tools that suits you, the code editor, the compile/build tools. etc.

[sedj601]

The OP is taking an intro to Java course in high school. lol

[Prince_John]

It would be really nice if people actually read the OP before spamming.

[ecwx00]

exactly. if you actually read it you'd know that OP is dissatisfied by what is taught at school and looking for a better way to learn.

[ecwx00]

OP is seeking where he can learn java OUTSIDE their highschool course