net.openhft.chronicle.core.time

Interface TimeProvider

All Known Implementing Classes:

PosixTimeProvider, SetTimeProvider, SystemTimeProvider, UniqueMicroTimeProvider

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface TimeProvider

Supplies wall clock timestamps in milliseconds, microseconds and nanoseconds.

Implementations typically delegate to the operating system clock, so the value returned can move backwards if the wall clock is corrected. Key implementations include PosixTimeProvider and SystemTimeProvider. The PosixTimeProvider is often preferred for its enhanced speed, accuracy and stability, though it relies on native code and thus may have platform specific dependencies.

This interface is crucial in contexts where precise time measurements are vital, such as in performance monitoring, timestamping events, or handling time-sensitive operations.

Use UniqueMicroTimeProvider if monotonic timestamps are required.

See Also:

PosixTimeProvider, SystemTimeProvider

Method Summary

Modifier and Type	Method and Description
default long	currentTimeMicros() Retrieves the current time in microseconds.
long	currentTimeMillis() Retrieves the current time in milliseconds.
default long	currentTimeNanos() Retrieves the current time in nanoseconds.

Method Detail

currentTimeMillis

long currentTimeMillis()

Retrieves the current time in milliseconds.

This method returns the current time with millisecond precision, measured from the Unix epoch (00:00:00 UTC on 1 January 1970). Implementations must guarantee thread-safe access.

Returns:

the current time in milliseconds since the Unix epoch

currentTimeMicros

default long currentTimeMicros()
                        throws IllegalStateException

Retrieves the current time in microseconds.

This default implementation offers microsecond precision by scaling the millisecond value from currentTimeMillis() by a factor of 1000. Implementations may override this for higher accuracy if available.

Returns:

the current time in microseconds since the Unix epoch

Throws:

IllegalStateException - if the time value cannot be accurately determined or converted

currentTimeNanos

default long currentTimeNanos()
                       throws IllegalStateException

Retrieves the current time in nanoseconds.

This default method provides nanosecond precision by further scaling the microsecond value from currentTimeMicros() by 1000. Implementations may provide more precise or direct measurements if their underlying system supports it.

Returns:

the current time in nanoseconds since the Unix epoch

Throws:

IllegalStateException - if the time value cannot be accurately determined or converted