Are parsers generated by ANTLR thread-safe? Can I parse multiple inputs concurrently?
Typically this question is really asking, "can I make multiple instances of the same parser and parse multiple input streams at the same time?" Emphatically, "yes". There are not global variables or shared static variables that would force all parsers to operate at different times.
You can have multiple parsers and multiple lexers all operating on the same input stream (to handle complicated input streams like java/javadoc comments), but a single thread should weave its way through all of them.