code: protected void addStringValue(Document doc, String fieldName, Object internalValue, boolean tokenized)
     {
        addStringValue(doc, fieldName, internalValue, tokenized, true, DEFAULT_BOOST, true);
     }
docs: Adds the string value to the document both as the named field and
  optionally for full text indexing if <code>tokenized</code> is
  <code>true</code>.
  
  @param doc           The document to which to add the field
  @param fieldName     The name of the field to add
  @param internalValue The value for the field to add to the document.
  @param tokenized     If <code>true</code> the string is also tokenized
  and fulltext indexed.