How to emit and execute Java bytecode at runtime?

I am writing an interpreter in Java for a domain-specific language with some scripting capabilities. I have already implemented a parser and now need to do a back end. To this end I am considering either to write my own interpreter (either working with abstract syntax trees or with some custom bytecodes) or target JVM (emit and execute Java bytecode at runtime).

Could someone with more experience in this area say how feasible is the approach of targeting JVM and what libraries would you recommend to use for emitting Java bytecode?