Trying to learn Java but failed miserably in all attempts

[SoapDish]

Hello,

 

I have started to learn Java about 1 year ago (I gave up... well... I rage quit after a ~6 months and wanted to get back to it almost instantly but my brain kept saying "nope").

In theory I can write some very basic things, also in theory I know what are the fields, classes, constructors, I know the data types, I can write tests, I even know some Spring  annotations and I think I understand them(!).

 

But in practice and in reality I never truly understood anything beyond hello world (strangely if you would show me some advanced code and say "finish it by adding Spring annotations" I will probably succed in doing it). I'm not able to write anything on my own as in reality I do not understand a thing. I tried to read the books and follow them in "practice mode", I tried some video tutorials for a very begginers, yet when it comes for me to write anything beyond hello world I change into mindless zombie. More about video tutorials - when I follow them everything seems to be cool and I feel the power, but as soon as I finish it and try to excersise on my own, my head is empty. I'm getting very frustrated about all of this as I'v always been a quick learner (I have an IQ of 136) and here I can't get a simple things.

 

 

 

  Quote

for(int i=0; i<10; i++)

Expand  

This for example. I know it is a part of the loop. And I know(?) it is some condition(?) for "for" statement. But thats it. I really don't know how the loop works, even though I wrote a lot of them when I followed the tutorials. Especially the "i++" part irritates me the most as always when I see it I'm like "what the hell is that i++, what is it doing, what does it means??".

 

Well, I simply can't understand the basics (the loop case is just one of the many) and no book, no video tutorial, and no practice helped me. I would really like to learn Java, and the most importantly I would like to understand at least the basics, especially since I have invested soo much time in it.

 

Could someone advise me how to learn all those things? Or how to understand them? (I tried to google my questions many times before but didn't find an answer) I would be really and eternally grateful.

 

Thank you in advance

Edited April 7, 2017 by SoapDish

[+Biscuits Brown MVC]

Consider for a moment how you end a line of code - with a semi colon (;) so what you have is essentially three little lines of code.

 

int i = 0;

i<10;

i++

 

You also know its a loop because of the for syntax so... you are creating a little integer that is your loop counter (int i) and setting it to 0.

Then you are saying while i < 10 meaning if i is less than 10 keep looping.

Finally i++. This means increment i by 1 ( i = i+1 ).

 

Does that help?

 

[SoapDish]

Yes. I have never seen such explaintion before, thank you!

 

Still looking for a cure for my problems though.

[Seahorsepip Veteran]

It's never the goal to understand every detail of all code, it's more important to understand the architecture.

 

Following tutorials is a great way to learn how to make a calculator when it's a tutorial about making a calculator but it's not that easy to use the same tutorial to make a sudoku solver as example.

 

So how do we learn to realize ideas into actual code?

 

Divide it, then divide it again, and again and again till the steps are so easy that it's no longer an issue to realize those steps.

 

1. Write your idea down.
   • e.g. Sudoku solver
2. Think about the global steps needed.
   • Values input
   • Calculate solution
   • Show solution
3. Divide those global steps in logical smaller steps and realise them, if needed look for solutions online.
   • Create a GUI with 9 input boxes
   • Get input values from GUI on button click
   • Look at algorithms for solving sudokus
   • Pick an algorithm
   • Realize this algorithm by dividing all logical steps and looking up the required code to realise each step and combining all the code.
   • Show the calculated values in the GUI by filling the empty input boxes.
4. Put everything together and you've made a sudoku solver

 

So why is dividing problems into small steps so important?

 

When you google "how to make a sudoku solver" you will not get any actual answer or just another tutorial. 

But when you google "how to store values from a sudoku?" and "how to loop through a 2 dimensional array" you get actual specific answers with code that is explained and makes sense since it's just a few lines of code instead of a whole program.

 

That's great but what about more complex programs?

 

Thereare multiple programming paradigms that fit different scenarios. A very common paradigm is OOP which stands for Object Oriented Programming, this makes it easier to work with data and logic by defining objects like a Car that has a color and a numberplate and can drive() but also brake().

 

What to do when I don't know how to program my logic in Java, C#, Python etc?

 

As I said before: Write down and divide!

Write your logic down using psuedo code as example, this is code you can make up yourself, if you don't know how to do a certain step in logic just write down a sentence describing what should be done by the computer. Then divide this psuedo code in small steps and look each step up, in most cases the solution is found quickly if not you can always post questions on this forum or sites like Stackoverflow.

 

Making diagrams also helps in the progress, illustrate your logical thinking steps and the data used in the application using logic flow diagrams and entity relationship diagrams.

 

Finding clear and educating answers for very specific questions is hard, divide it and look for the answers for smaller questions instead.

 

Programming is like a journey, it's a matter of dividing the problem is smaller and smaller steps and solving those steps like a puzzle.

 

 

TL;DR

I type too much when I'm stuck in a train.

[Andre S. Veteran]

Sounds like someone tried to teach you programming by starting with classes and unit tests rather than basic control flow statements. I saw that before and it was a Java class indeed.

 

Try to find a course that does the opposite? You could even just use a more beginner-friendly language like Python; tutorials tend to be proceed more logically. It's highly popular in teaching institutions. https://www.python.org/

 

You can start coding right away without installing anything here: https://repl.it/languages/python

[DevTech]

Something to keep in mind is that programming computers is NOT for everyone despite the attempts by various organizations to encourage everyone to do it such as "Hour of Code"

 

You can train a brain to do almost anything, but for most people, most things feel like lifting a weight up the hill and when they find their "thing" it becomes a welcome downhill relief. Programming may simply not be your "thing"

 

That being said most online education is terrible and most university education competes for the same "terrible" award. So if you feel it is something you really want to do then find a teaching style that matches your own learning style. From your example, you seem like you might be a "hands on" type of learner and would benefit greatly from some sort of Raspberry Pi type kit that turns lights on and off by using basic Machine Language (Assembly Programming) so that you can get a feel for exactly what the CPU is doing before you move up to all of the crazy Abstractions and Metaphors that "simplify" programming.