org.ehcache.expiry

Interface Expiry<K,V>

Type Parameters:

K - the type of the keys used to access data within the cache

V - the type of the values held within the cache

public interface Expiry<K,V>

A policy object that governs expiration for a Cache.

Previous values are not accessible directly but are rather available through a value supplier to indicate that access can be require computation such as deserialization.

See Expirations for common instances.

Method Summary

Modifier and Type	Method and Description
Duration	getExpiryForAccess(K key, ValueSupplier<? extends V> value) Get the expiration period (relative to the current time) when an existing entry is accessed from a Cache
Duration	getExpiryForCreation(K key, V value) Get the expiration period (relative to the current time) when a entry is initially added to a Cache
Duration	getExpiryForUpdate(K key, ValueSupplier<? extends V> oldValue, V newValue) Get the expiration period (relative to the current time) when an existing entry is updated in a Cache NOTE: Some cache configurations (eg.

Method Detail

getExpiryForCreation

Duration getExpiryForCreation(K key,
                              V value)

Get the expiration period (relative to the current time) when a entry is initially added to a Cache

Parameters:

key - the key of the newly added entry

value - the value of the newly added entry

Returns:

a non-null Duration

getExpiryForAccess

Duration getExpiryForAccess(K key,
                            ValueSupplier<? extends V> value)

Get the expiration period (relative to the current time) when an existing entry is accessed from a Cache

Parameters:

key - the key of the accessed entry

value - a value supplier for the accessed entry

Returns:

the updated expiration value for the given entry. A null return value indicates "no change" to the expiration time

getExpiryForUpdate

Duration getExpiryForUpdate(K key,
                            ValueSupplier<? extends V> oldValue,
                            V newValue)

Get the expiration period (relative to the current time) when an existing entry is updated in a Cache NOTE: Some cache configurations (eg. caches with eventual consistency) may use local (ie. non-consistent) state to decide whether to call getExpiryForUpdate() vs. getExpiryForCreation(). For these cache configurations it is advised to return the same value from both of these methods

Parameters:

key - the key of the updated entry

oldValue - a value supplier for the previous value of the entry

newValue - the new value of the entry

Returns:

the updated expiration value for the given entry. A null return value indicates "no change" to the expiration time