private void updateFileEntry(GhidraFile df, String id, String newPath) {
		if (id != null) {
			String oldPath = fileIdToPathIndex.get(id);
			if (oldPath == null) {
				fileIdToPathIndex.put(id, newPath);
			}
			else if (oldPath.equals(newPath)) {
				return;
			}
			else {
				GhidraFile oldDf = (GhidraFile) projectData.getFile(oldPath);
				if (oldDf == null) {
					fileIdToPathIndex.put(id, newPath);
				}
				else {
					reconcileFileIDConflict(df, oldDf);
				}
			}
		}
	}
Helper class to maintain mapping of fileID's to DomainFile's.
Ghidra/Framework/Project/src/main/java/ghidra/framework/data/DomainFileIndex.java