public boolean removeHandler(String columnName){
  if (m_overrides == null)   return false;
 else   return m_overrides.remove(columnName) != null;
}

public boolean removeHandler ( String columnName ) { if ( m_overrides == null ) return false ; else return m_overrides . remove ( columnName ) != null ; }
remove a custom data handler for a given column name . subsequent to this method , the column will use the default handler .
