About source code
If you are using default H2 database, you can use any JDBC viewer to open the database file. Note that you need to stop Traccar first because H2 doesn't allow simultaneous access from two processes.
If you are using default H2 database, you can use any JDBC viewer to open the database file. Note that you need to stop Traccar first because H2 doesn't allow simultaneous access from two processes.
T55ProtocolDecoder.java
Not sure if I understand the question. You can change file path in the config.
Most likely you are looking for DataManager.java.