public interface Criteria
ResultSets via ResultSet.applyFilter().
  Client- and server-side systems built into Smart GWT understand two criteria formats by default: simple key-value
 pairs (Criteria) or the AdvancedCriteria format.   
 Use DataSource.combineCriteria() to combine two Criteria objects
 (including Criteria and AdvancedCriteria) or DataSource.convertCriteria() to convert simple Criteria to the AdvancedCriteria format. 
  When sent to the Smart GWT
 server, the Java representation of the criteria is described here. 
 When sent to other servers, the operationBinding.dataProtocol affects the
 format.