private String getOldFileNameFromSymlink() {
            if(symlinkName == null) return null;
            try {
                return Paths.get(fileName).resolveSibling(symlinkName).toRealPath().toString();
            } catch (IOException e) {
                return null;
            }
        }
Name files by date - create a symlink with a constant name to the newest file
container-core/src/main/java/com/yahoo/container/logging/LogFileHandler.java