Language Processing

So I am writing a Java program that needs some language parsing. This language parsing is meant to be extended and modified in the near future. The thing is, i already know how to flex/bison this shit, but I think that flex and bison are shit, so I don't want to use them. Alternatives?

tl/dr: flex and bison are shit, what can i use instead?

>>7
What kind of language is he going to parse? Natural language? A DSL? A programming language? Is its grammar context-free? Is the grammar left recursive? Is the grammar ambiguous? Not enough context.