public List/*<Filter>*/ getFilters(String filterExpression) {
        if(_filters == null || filterExpression == null)
            return null;
        else return lookupFilters(filterExpression);
    }
public List getFilters ( String filterExpression ) { if ( _filters == null || filterExpression == null ) return null ; else return lookupFilters ( filterExpression ) ; }
Get a {@link List} of {@link Filter} objects.  The list returned will contain
all of the {@link Filter} objects whose {@link Filter#getFilterExpression()} matches the given
<code>filterExpression</code>.
@param filterExpression the expression whose matching filters to find
@return <code>null</code> if no matching {@link Filter} objects are found; a {@link List} of {@link Filter}
objects otherwise.