The basics are easy and learner-friendly.🤗
There is JShell helping to do Java without any tools.
There is a humongous community (12 millions Java developers) which provides help too.
The “darkside” is the monstrous ecosystem, say nobody can say they know it all about Java. Just Java EE (now Jakarta EE) is the biggest code grouping I know.
That’s why when you speak about Java, you might speak of subjects of different complexity. Take Android and EJBs: both are typical Java assets, but their purpose and difficulty are not at all comparable.
So, you could learn the basics fast; but the next steps might be more challenging.🙂