public function addFilter($filter) {
		if($this->filter === null) {
			$this->filter = $filter;
		} else {
			$this->filter->addNext($filter);
		}
	}
public function addFilter($filter) {
		if($this->filter === null) {
			$this->filter = $filter;
		} else {
			$this->filter->addNext($filter);
		}
	}
public function addFilter ( $ filter ) { if ( $ this -> filter === null ) { $ this -> filter = $ filter ; } else { $ this -> filter -> addNext ( $ filter ) ; } }
Adds a filter to the end of the filter chain.
@param LoggerFilter $filter add a new LoggerFilter
Adds a filter to the end of the filter chain .