I want to train a MaxEnt classifier over a training corpus. My features are syntactical and semantical like POS tags or NER tags and so on. Is there any MaxEnt classifier implementation in Java that support defining such features?
The Apache OpenNLP library has a maxent package. In addition, it features a wide range of methods for Named Entity Recognition and Part-of-Speech tagging, among other tasks, so it will probably satisfy your needs.