javax.realtime

Interface Chronograph

All Known Implementing Classes:

Clock

public interface Chronograph

The interface for all devices that support the measurement of time with great accuracy.

Since:

RTSJ 2.0

Method Summary

Modifier and Type	Method and Description
RelativeTime	getEpochOffset() Determines the time on the UTC clock when this chronograph was zero.
RelativeTime	getEpochOffset(RelativeTime dest) Determines the difference between the epoch of this clock from the Epoch.
RelativeTime	getQueryPrecision() Obtain the precision with which time can be read, i.e., the nominal interval between ticks.
RelativeTime	getQueryPrecision(RelativeTime dest) Obtain the precision with which time can be read, i.e., the nominal interval between ticks.
AbsoluteTime	getTime() Determines the current time.
AbsoluteTime	getTime(AbsoluteTime dest) Obtain the current time.

Method Detail

getEpochOffset

RelativeTime getEpochOffset()
                     throws UnsupportedOperationException,
                            UninitializedStateException

Determines the time on the UTC clock when this chronograph was zero.

Throws:

UnsupportedOperationException - when the chronograph does not have the concept of date.

UninitializedStateException - when UTC time is not yet available.

Returns:

A newly allocated RelativeTime object in the current execution context with the realtime clock as its chronograph and containing time when this chronograph was zero.

getEpochOffset

RelativeTime getEpochOffset(RelativeTime dest)
                     throws StaticUnsupportedOperationException,
                            UninitializedStateException

Determines the difference between the epoch of this clock from the Epoch. For the UTC, the result is always a RelativeTime value equal to zero. For other clocks, it is a value representing the difference between zero on that clock and zero on the UTC measured on the UTC.

Throws:

StaticUnsupportedOperationException - when the chronograph does not have the concept of date.

UninitializedStateException - when UTC time is not yet available.

Parameters:

dest - An instance of RelativeTime object which will be updated in place.

Returns:

the instance of RelativeTime passed as parameter, or a new object when dest is null. The returned object represents the time differnce between its associated chronograph and the Epoch.

getTime

AbsoluteTime getTime()

Determines the current time. This method returns an absolute time value representing the chronograph's notion of absolute time. For chronographs that do not measure calendar time, this absolute time may not represent a wall clock time.

Returns:

A newly allocated instance of AbsoluteTime in the current allocation context, representing the current time. The returned object has this its chronograph.

getTime

AbsoluteTime getTime(AbsoluteTime dest)

Obtain the current time. The time represented by the given AbsoluteTime is changed at some time between the invocation of the method and the return of the method. This method will return an absolute time value that represents this chronograph's notion of the absolute time. For chronographs that do not measure calendar time, this absolute time may not represent a wall clock time.

Parameters:

dest - The instance of AbsoluteTime object which will be updated in place.

Returns:

The instance of AbsoluteTime passed as parameter, or a new object when dest is null. The returned object represents the current time and is associated with this chronograph.

getQueryPrecision

RelativeTime getQueryPrecision()

Obtain the precision with which time can be read, i.e., the nominal interval between ticks. It is the same as calling getQueryPrecision(RelativeTime) with null as an argument.

Returns:

a newly allocated time value holding the read precision.

getQueryPrecision

RelativeTime getQueryPrecision(RelativeTime dest)

Obtain the precision with which time can be read, i.e., the nominal interval between ticks.

Parameters:

dest - is a time object in which to return the results.

Returns:

the read precision in dest, when dest is not null, or in a newly created object otherwise.