original_string: public function setDocumentDistributorCallback($callback)
      {
          if ($callback !== null  &&  !is_callable($callback)) {
              include_once 'Zend/Search/Lucene/Exception.php';
              throw new Zend_Search_Lucene_Exception('$callback parameter must be a valid callback.');
          }
  
          $this->_documentDistributorCallBack = $callback;
      }
code: public function setDocumentDistributorCallback($callback)
      {
          if ($callback !== null  &&  !is_callable($callback)) {
              include_once 'Zend/Search/Lucene/Exception.php';
              throw new Zend_Search_Lucene_Exception('$callback parameter must be a valid callback.');
          }
  
          $this->_documentDistributorCallBack = $callback;
      }
code_tokens: public function setDocumentDistributorCallback ( $ callback ) { if ( $ callback !== null && ! is_callable ( $ callback ) ) { include_once 'Zend/Search/Lucene/Exception.php' ; throw new Zend_Search_Lucene_Exception ( '$callback parameter must be a valid callback.' ) ; } $ this -> _documentDistributorCallBack = $ callback ; }
docstring: Set callback for choosing target index.
  
  @param  callback $callback
  @throws Zend_Search_Lucene_Exception
docstring_tokens: Set callback for choosing target index .