Replacement for {@link ca.uhn.hl7v2.util.MessageIDGenerator}. You should not use this class directly, however, but wrap it into a {@link DelegatingHiLoGenerator} generator. Its primaryimprovement over {@link ca.uhn.hl7v2.util.MessageIDGenerator} is that you can set path and filename.
Reading and writing to the file is thread-safe, however, you should not use the same file from different Java processes because no read/write locks are being checked.