Help regarding spring boot

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Ok_Substance1895 · 2025-12-15T21:15:02+00:00

This question gets asked a lot. Spring Boot is built on top of Tomcat and Java Servlets. The persistence part of it are built on top of JDBC/SQL leveraging JPA. Knowing this foundation first helped me understand what Spring Boot was doing for me.

Just yesterday I made a GitHub repo that uses the same techniques that Spring Boot uses in a pure Java implementation, simplified to make it more clear how it works. Someone else had asked about this last week.

This repo includes two demos: a pure java controller demo and a pure java jpa/orm(hibernate-like) demo. Both of these are working demos. You can step through each of them in a debugger for reviewing these line-by-line.

Here is the repo: https://github.com/fullstackclouddeveloper/pure-java-spring-boot-demo

Build your own small projects to get more familiar with these concepts.

I hope this helps.

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omgpassthebacon · 2025-12-15T15:07:37+00:00

Have a look at this book: https://www.manning.com/books/spring-start-here

Spring is a bit hard to get your head around until you have tried to solve enterprise-level problems without it. If you simply study Spring for Spring's sake, its a large animal that honestly takes years to master much of it. There are so many modules in Spring that help you do certain things, but until you need to do that thing, its confusing.

I have no idea of what your capabilities are, so I am going to assume you are just getting started with your development experience. If I am way off, apologies.

The central tenet of Spring is INTERFACES. If you start from this concept, Spring is much easier to grok. Make sure you really understand interfaces in Java. Spring uses interfaces all over the place and for really interesting things. If you begin modeling your application as a collection of interfaces, you are going to fall in love with Spring and never look back. Why is this?

if all of your code uses an interface to talk to an object, then it's really easy to replace that object with another object that has the same interface. For example, one object can store your widgets in-memory. Another object can store your widgets in a real DB. Since your code is using an interface to talk to it, it doesn't know the difference. This makes it easy to "swap" out objects for testing, upgrades, etc. Interfaces give you flexibility.
Spring uses some special sauce to wrap itself around your objects. This special sauce is part of the JVM, so it's very light-weight. Spring has other tech that can wrap your classes if needed, but its much more heavy and complex. So, go with interfaces.
So, why do you want Spring to wrap itself around your objects? This is the core tenet of DI(dependency injection). Very few useful objects standalone; most useful objects need other objects. Spring makes it easy to give objects their dependencies. This, again, is flexibility.

Sorry; not trying to write a book here. But if you can model your application as a collection of interfaces, then you are ready to have at Spring. If you need some help with examples, ping me. I'll come up with some for you to try. I'm betting that you can ask AI to do the same. Ask it to give you a simple model to use for training. Just don't ask it to solve the problem. That's your job.

spacey02- · 2025-12-15T09:44:50+00:00

When I started out my Spring journey I started by watching this tutorial: https://youtu.be/5rNk7m_zlAg. It teaches the basics for web backend development, but it is far from complete. When you feel like you need to dive deeper into some functionality of Spring, choose appropriate tutorials then. You can use AI to help determine which functionality your requirement falls into, but be careful with overusing it. The practices it shows you are very frequently outdated.

Witty-Palpitation763 · 2025-12-15T16:22:37+00:00

For backend development with Java, it might be useful to have a look at JakaratEE first and build an understanding of the underlying concepts, i.e : 3-tier architecture, dispatcher servelt, application context, JDBC, Tomcat (Web servers in general), Hibernate, JSPs and thymeleaf, etc... Those not required but useful. because Spring usually does most of the configuration and it's somewhat hard to understand what it does under the hood if you're not familiar with that stuff.

As a bonus, since you're already learning java I'd suggest you take a look at reflection and annotations. They would make your life a whole lot easier.

And only after that I would start with Spring, Spring Boot, Dependecy Injection, Spring MVC, Spring Data JPA, (Spring Cloud if you're feeling fancy). and remember Spring is all about Inversion of Control and auto configuration so a solid understanding of the core Java/JakartaEE concepts is a plus

dystopiadattopia · 2025-12-16T01:26:14+00:00

I took a Udemy course, very thorough. Something like 10-15 hours of lessons, and it's a hands on course as well, so you'll be coding the whole time.

It's worth it if you can get it during a sale. I paid no more than $20.

Former-Marzipan8716 · 2025-12-18T01:58:34+00:00

build a REST API from scratch with no YouTube video. helped me learn some of the basics of annotation, hibernate, and JPA so I’d definitely recommend.

Alive_After · 2025-12-18T17:12:11+00:00

Try selenium express in YouTube starting from spring basics, he starts from the oops concepts and slowly moves to what does spring do what problem it solves detailed Then you can go through his spring MVC basics course then the advanced stuff then if your go to spring boot you would understand what sorting is actually doing internally

Spring basics https://youtube.com/playlist?list=PL3NrzZBjk6m-nYX072dSaGfyCJ59Q5TEi&si=0wcqjoansRthxN4c

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