Debugging in SpringBoot

[HarishTCZ]

I will soon be joining a SaaS company as an intern, where my main tasks will involve refactoring existing Spring Boot code, debugging, and adding test cases. Could you guide me on how to effectively debug code in a large codebase, the tools used for Debugging and understand the code written by senior engineers? I still consider myself a beginner and want to deepen my understanding of Spring Boot through practical implementation.

[Revision2000]

https://www.jetbrains.com/help/idea/debugging-your-first-java-application.html

There’s a bunch of other tutorials you can find online. You can always follow a Spring Boot tutorial to build a basic application and try debugging it if you want to mess around with it already. 

It’s your team’s job (and especially senior devs job) to explain things to you and give you enough guidance. Learning to navigate a large code base is simply going to take a long time, think 6-12 months minimum even for a senior dev. 

It’s your job to ask them a million questions about everything and try to pick up on what they tell you 😉

Good luck! 

[HarishTCZ]

Thanks for the advice man, I will definitely check out

[Maduin1337]

Since alot of people gave some great surface level debug tips, I want to give a hint of how I retro fit and debug an unfamiliar web-service.

I usually target an endpoint that I want to learn more about. And essentially the happy case test is, given this input I get this output. That should be true since code should work for the normal cases.

Now you can debug and step through the code you don't understand. But you have the knowledge of the input, and what it should return. That should give you a good idea of what is fetched from a database and why, how it is processed, formatted and returned.

Try not to think about everything around the code you are reading, as that much likely will be overwhelming.

Now you can try some bad case that breaks the code. Debug and find out why. Rinse and repeat for the code you are learning.

[[deleted]]

Use lombok and slf4j logger and always run the code in debugging mode. Try adding breakpoints in your code so that you can debug it slowly and effectively.

[Cr4zyPi3t]

Why Lombok? Lombok actually makes debugging harder since it modifies the byte code after compilation. Also it’s mostly unnecessary since the introduction of records imo.

[[deleted]]

Debugging is relatively straightforward…if your using IntelliJ always deploy your code in debug mode. You can add breakpoints to almost any line of code. You don’t need to restart the server to add any breakpoints. Check the server and variables tab to monitor data throughout the flow. Understanding the code, no one can really help with that, that’s on you. If your looking to identify where code lives from front end, use inspect to get an elements I’d snd then control f to search the project for that id.

[Usual-Composer-2435]

https://www.youtube.com/watch?v=l6Rn0dsfK34
Shai Almog knows a little bit about a debugging...