| Class | 
                        Description | 
                    
                            | 
                                
                                    BaseDuration
                                
                             | 
                            Base class for date and time durations. | 
                        
                            | 
                                
                                    BaseDuration.From
                                
                             | 
                             | 
                        
                            | 
                                
                                    DatumDependentDuration
                                
                             | 
                            DatumDependentDuration represents durations whose length in milliseconds 
 cannot be determined without knowing the datum point. | 
                        
                            | 
                                
                                    Duration
                                
                             | 
                            Duration represents time periods which have values independent of the context.
  | 
                        
                            | 
                                
                                    TimeCategory
                                
                             | 
                            Apply a number of methods to allow convenient Date/Time manipulation,such as:
 
 use (groovy.time.TimeCategory) {
     // application on numbers:
     println 1.minute.from.now
     println 10.hours.ago | 
                        
                            | 
                                
                                    TimeDatumDependentDuration
                                
                             | 
                            TimeDatumDuration represents a time period which results from an
 arithmetic operation between a TimeDuration object and a DatumDuration object | 
                        
                            | 
                                
                                    TimeDuration
                                
                             | 
                            TimeDuration represents time periods expressed in units of hours, minutes,
 seconds and milliseconds. |