Backend development: Java

Sefism.Backend development: Java

Tauseef Fayyaz

A to Z

Glossary

Every concept in this sheet, plus the smaller terms it uses. Select a concept to open its card.

E

Exceptions and @RestControllerAdvice: A @RestControllerAdvice class maps exceptions thrown anywhere in controllers to HTTP responses.

G

Git commits and branches: Git records snapshots of your project as commits.

J

Java basics: types, classes and objects: Java is statically typed.
Java collections: The Collections Framework gives the List, Map and Set interfaces with implementations such as ArrayList, HashMap and HashSet, plus streams for filtering and mapping.

M

Maven and Gradle builds: Build tools that download dependencies, compile, run tests and package the app as a runnable JAR.

P

Pull requests: A pull request proposes merging a branch into main and shows the diff, CI results and review comments in one place.

R

Records: A record is a compact, immutable data class: the compiler writes the constructor, accessors, equals, hashCode and toString.

S

Spring beans and dependency injection: Spring creates objects (beans) for classes annotated @Service, @Repository or @RestController and passes their dependencies through the constructor.

T

Terminal essentials: A shell runs commands such as cd, ls, cat, grep and curl, and pipes (|) feed one command's output into the next.

V

Virtual threads: Lightweight threads managed by the JVM (Java 21+).