How to improve programming skills as a Junior without Senior [duplicate]

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• Is it must for a junior Programmer to have a mentor? [closed] 5 answers

At the moment I'm 23 and working as a junior programmer at a software service provider. While I'm really happy with my job and my colleagues, I sometimes would love to have someone who could tell me what is bad about my code (architecture and so on), why it is bad AND what could I do to make it better.

As we have no senior java programmers anymore (I'm the last one who can program java), I would love to get your advice about becoming a better programmer.

Disclaimer: Sometimes I ask my non java programmer colleagues if my code is "good" or "bad" but I have the feeling that they can't judge because they aren't java programmers. (They hardly program anything)

Are there any communities which are happy to mentor junior developers? Would it help if I read tons of books? Any advice how I can improve my existing skills and learn if what I'm doing is bad or good?

Epilog:

I didn't even think about switching the employer back in May when I asked this question but what all of you said was stuck in my head and I decided to switch in April. I now found a new employer and I got a position as a junior Java developer at the new company. I hope my professional growth will get better in future with my new employer.

I just wanted to say thank you for all of your advices.