All Known Implementing Classes:

TimeReference.Default, TimeReference.Milliseconds
```
public interface TimeReference
```
Time reference for a cache. By default, the current time is retrieved with System.currentTimeMillis(). Another time reference can be specified if the application uses a different time source or when a simulated clock should be used.
For efficiency reasons cache2k always uses a long to store a time value internally. The resolution is expected to be milliseconds or higher. There is currently no intensive testing carried out with different timer resolutions.
An instance may implement AutoCloseable if resources need to be cleaned up.

Author:

Jens Wilke

Nested Class Summary

Nested Classes
Modifier and Type Interface Description

static class TimeReference.Default

static class TimeReference.Milliseconds

Field Summary

Fields
Modifier and Type	Field	Description
`static TimeReference`	`DEFAULT`	Default implementation using `System.currentTimeMillis()` as time reference.
`static long`	`MINIMUM_TICKS`	Every time reference is expected to produce times higher or equal to this value.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`sleep(long ticks)`	Wait for the specified amount of time.
`long`	`ticks()`	Returns the timer ticks since a reference point, typically milliseconds since epoch.
`Instant`	`ticksToInstant(long timeInTicks)`	Convert a time value in ticks to an instant object.
`long`	`ticksToMillisCeiling(long ticks)`	Convert a duration in ticks to milliseconds, rounding up to the next full millisecond.
`long`	`toTicks(Duration v)`	Convert a duration to ticks.

- Field Detail
  - MINIMUM_TICKS
```
static final long MINIMUM_TICKS
```
    Every time reference is expected to produce times higher or equal to this value. cache2k uses lower values for expired or invalid entries, which must be guaranteed in the past.
    
    See Also:
    
    Constant Field Values
  - DEFAULT
```
static final TimeReference DEFAULT
```
    Default implementation using System.currentTimeMillis() as time reference.
- Method Detail
  - ticks
```
long ticks()
```
    Returns the timer ticks since a reference point, typically milliseconds since epoch. Expected to be always equal or higher than 100L.
  - sleep
```
void sleep(long ticks)
    throws InterruptedException
```
    Wait for the specified amount of time. This is only executed by tests and never by the cache itself.
    The value of 0 means that the thread should pause and other processing should be done. In a simulated clock this would wait for concurrent processing and, if no processing is happening, advance the time to the next event.
    
    Throws:
    
    InterruptedException
  - ticksToMillisCeiling
```
long ticksToMillisCeiling(long ticks)
```
    Convert a duration in ticks to milliseconds, rounding up to the next full millisecond.
    This can be overridden in case another timescale is used. Conversion is needed for correctly scheduling a timer tasks.
  - toTicks
```
long toTicks(Duration v)
```
    Convert a duration to ticks. Used to convert configuration durations.
  - ticksToInstant
```
Instant ticksToInstant(long timeInTicks)
```
    Convert a time value in ticks to an instant object. Needed for display purposes.

Modifier and Type	Interface	Description
`static class`	`TimeReference.Default`
`static class`	`TimeReference.Milliseconds`

Interface TimeReference

Nested Class Summary

Field Summary

Method Summary

Field Detail

MINIMUM_TICKS

DEFAULT

Method Detail

ticks

sleep

ticksToMillisCeiling

toTicks

ticksToInstant