code: public int findFieldOffsetForPath(final String fieldPath) {
      for (final JBBPNamedFieldInfo f : this.namedFieldData) {
        if (f.getFieldPath().equals(fieldPath)) {
          return f.getFieldOffsetInCompiledBlock();
        }
      }
      throw new JBBPIllegalArgumentException("Unknown field path [" + fieldPath + ']');
    }
docs: Find offset of a field in the compiled block for its field path.
  
  @param fieldPath a field path, it must not be null
  @return the offset as integer for the field path
  @throws JBBPException if the field is not found