code: private String trimPrefix(final String className) {
      for (final String prefix : this.dropPrefix) {
        if (className.startsWith(prefix)) {
          return className.substring(prefix.length());
        }
      }
      return className;
    }
docs: Check if the class name starts with one of the prefixes specified in `dropPrefix`,
  and remove it. e.g. for class name `org.apache.reef.util.logging.Config` and
  prefix `com.microsoft.` (note the trailing dot), the result will be
  `reef.util.logging.Config`