Package io.deephaven.base.clock

Interface SystemClock

All Superinterfaces:

Clock

All Known Implementing Classes:

SystemClockMillis, SystemClockUtc

public interface SystemClock
extends Clock

A marker interface for Clock that designates implementations as system clocks.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DEFAULT
static final String	KEY
static final String	SERVICE_LOADER
static final String	SYSTEM_MILLIS
static final String	SYSTEM_UTC

Method Summary

Static Methods

Modifier and Type	Method	Description
static SystemClock	of()	Creates a new system clock, or returns the singleton instance, based on system property "deephaven.systemClock" (uses "default" if not present).
static Optional<SystemClock>	serviceLoader()	Uses ServiceLoader.load(Class) with SystemClock.class to load a system clock.
static SystemClock	systemMillis()	The system clock, based off of System.currentTimeMillis().
static SystemClock	systemUTC()	The system clock, based off of Clock.systemUTC().

Methods inherited from interface io.deephaven.base.clock.Clock

currentTimeMicros, currentTimeMillis, currentTimeNanos, instantMillis, instantNanos

Field Details

KEY

static final String KEY

See Also:

• Constant Field Values

DEFAULT

static final String DEFAULT

See Also:

• Constant Field Values

SERVICE_LOADER

static final String SERVICE_LOADER

See Also:

• Constant Field Values

SYSTEM_UTC

static final String SYSTEM_UTC

See Also:

• Constant Field Values

SYSTEM_MILLIS

static final String SYSTEM_MILLIS

See Also:

• Constant Field Values

Method Details

of

static SystemClock of()
               throws ClassNotFoundException,
NoSuchMethodException,
InvocationTargetException,
InstantiationException,
IllegalAccessException

Creates a new system clock, or returns the singleton instance, based on system property "deephaven.systemClock" (uses "default" if not present).

Property Value	Logic
"default"	serviceLoader().orElse(systemUTC())
"serviceLoader"	serviceLoader().orElseThrow()
"systemUTC"	systemUTC()
"systemMillis"	systemMillis()
value	(SystemClock) Class.forName(value).getDeclaredConstructor().newInstance()

Returns:

a new instance of the system clock

Throws:

ClassNotFoundException

NoSuchMethodException

InvocationTargetException

InstantiationException

IllegalAccessException

See Also:

• systemUTC()
• systemMillis()
• serviceLoader()

systemUTC

static SystemClock systemUTC()

The system clock, based off of Clock.systemUTC().

Returns:

the system clock

See Also:

• SystemClockUtc

systemMillis

static SystemClock systemMillis()

The system clock, based off of System.currentTimeMillis().

Returns:

the millis-based system clock

See Also:

• SystemClockMillis

serviceLoader

static Optional<SystemClock> serviceLoader()

Uses ServiceLoader.load(Class) with SystemClock.class to load a system clock.

If a ServiceConfigurationError is thrown, the error will be logged to System.err and Optional.empty() will be returned.

Returns:

the service loader system clock

Throws:

IllegalStateException - if more than one system clock is registered