javax.cache.expiry

Interface ExpiryPolicy<K,V>

Type Parameters:

K - the type of keys

V - the type of values

All Known Implementing Classes:

AccessedExpiryPolicy, CreatedExpiryPolicy, EternalExpiryPolicy, ModifiedExpiryPolicy, TouchedExpiryPolicy

public interface ExpiryPolicy<K,V>

Defines functions to determine when cache entries will expire based on creation, access and modification operations.

Each of the functions return a new Duration that of which specifies the amount of time that must pass before a cache entry is considered expired.

Author:

Brian Oliver, Greg Luck

Method Summary

Methods

Modifier and Type	Method and Description
Duration	getExpiryForAccessedEntry(Cache.Entry<? extends K,? extends V> entry) Gets the duration before the accessed Cache.Entry is considered expired.
Duration	getExpiryForCreatedEntry(Cache.Entry<? extends K,? extends V> entry) Gets the duration before the newly Cache.Entry is considered expired.
Duration	getExpiryForModifiedEntry(Cache.Entry<? extends K,? extends V> entry) Gets the duration before the modified Cache.Entry is considered expired.

Method Detail

getExpiryForCreatedEntry

Duration getExpiryForCreatedEntry(Cache.Entry<? extends K,? extends V> entry)

Gets the duration before the newly Cache.Entry is considered expired.

This method is called by the caching implementation after a Cache.Entry is created, but before the said entry is added to a cache, to determine the Duration before the said entry expires. If a Duration.ZERO is returned the Cache.Entry is considered to be already expired and will not be added to the Cache.

Should an exception occur while determining the Duration, an implementation specific default Duration will be used.

Parameters:

entry - the cache entry that was created

Returns:

the new duration until the entry expires

getExpiryForAccessedEntry

Duration getExpiryForAccessedEntry(Cache.Entry<? extends K,? extends V> entry)

Gets the duration before the accessed Cache.Entry is considered expired.

This method is called by the caching implementation after a Cache.Entry is accessed to determine the Duration before the said entry expires in the future. If a Duration.ZERO is returned the Cache.Entry will be considered expired for future access. Returning null will result in no change to the previously understood expiry Duration.

Should an exception occur while determining the Duration, an implementation specific default Duration will be used.

Parameters:

entry - the cache entry that was accessed

Returns:

the new duration until the entry expires

getExpiryForModifiedEntry

Duration getExpiryForModifiedEntry(Cache.Entry<? extends K,? extends V> entry)

Gets the duration before the modified Cache.Entry is considered expired.

This method is called by the caching implementation after a Cache.Entry is modified to determine the Duration before the updated entry expires. If a Duration.ZERO is returned the Cache.Entry is considered already expired. Returning null will result in no change to the previously understood expiry Duration.

Should an exception occur while determining the Duration, an implementation specific default Duration will be used.

Parameters:

entry - the cache entry that was modified

Returns:

the new duration until the entry expires