@Override
	public void programReady(OpenMode openMode, int currentRevision, TaskMonitor monitor)
			throws IOException, CancelledException {
		if (openMode != OpenMode.UPGRADE) {
			return;
		}
		if (upgradeOldExtRefAdapter(monitor)) {
			return;
		}
	}
Constructs a new ExternalManagerDB
@param handle the open database handle
@param addrMap the address map
@param openMode the program open mode.
@param lock the program synchronization lock
@param monitor the progress monitor used when upgrading
@throws CancelledException if the user cancelled while an upgrade was occurring
@throws IOException if a database io error occurs.
@throws VersionException if the database version does not match the expected version
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/external/ExternalManagerDB.java