io.werval.spi.cache

Class CacheAdapter

java.lang.Object

io.werval.spi.cache.CacheAdapter

All Implemented Interfaces:

Cache

Direct Known Subclasses:

MapCache

public abstract class CacheAdapter
extends Object
implements Cache

Cache Adapter.

Default behaviour and Metrics handling (hits, misses, updates and removes meters).

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CacheAdapter.CacheEvent Cache Event.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	CacheAdapter() Create a Cache without metrics handling.
protected	CacheAdapter(Function<CacheAdapter.CacheEvent,CacheAdapter.CacheEvent.Closeable> handler) Create a Cache with metrics handling.

Method Summary

Modifier and Type	Method and Description
protected abstract <T> T	doGet(String key) Concrete GET.
protected abstract void	doRemove(String key) Concrete REMOVE.
protected abstract <T> void	doSet(int ttlSeconds, String key, T value) Concrete SET.
<T> T	get(String key) Fetch cached object for a given key.
<T> Optional<T>	getOptional(String key) Optionaly fetch cached object for a given key.
<T> T	getOrSetDefault(String key, int ttlSeconds, Supplier<T> defaultValueSupplier) Fetch cached object for a given key or set an expiring default value.
<T> T	getOrSetDefault(String key, int ttlSeconds, T defaultValue) Fetch cached object for a given key or set an expiring default value.
<T> T	getOrSetDefault(String key, Supplier<T> defaultValueSupplier) Fetch cached object for a given key or set a non-expiring default value.
<T> T	getOrSetDefault(String key, T defaultValue) Fetch cached object for a given key or set a non-expiring default value.
boolean	has(String key) Check if the Cache has an object for a given key.
void	remove(String key) Remove a Cache entry.
<T> void	set(int ttlSeconds, String key, T value) Set an expiring object for a given key in the Cache.
<T> void	set(String key, T value) Set a non-expiring object for a given key in the Cache.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CacheAdapter

protected CacheAdapter()

Create a Cache without metrics handling.

CacheAdapter

protected CacheAdapter(Function<CacheAdapter.CacheEvent,CacheAdapter.CacheEvent.Closeable> handler)

Create a Cache with metrics handling.

Parameters:

handler - Metrics handler

Method Detail

has

public final boolean has(String key)

Description copied from interface: Cache

Check if the Cache has an object for a given key.

Specified by:

has in interface Cache

Parameters:

key - Cache Key

Returns:

true if the cache has an object for the given key

get

public final <T> T get(String key)

Description copied from interface: Cache

Fetch cached object for a given key.

Specified by:

get in interface Cache

Type Parameters:

T - Object Type

Parameters:

key - Cache Key

Returns:

The cached object for the given key, or null if absent

getOptional

public final <T> Optional<T> getOptional(String key)

Description copied from interface: Cache

Optionaly fetch cached object for a given key.

Specified by:

getOptional in interface Cache

Type Parameters:

T - Object Type

Parameters:

key - Cache Key

Returns:

An Optional of the cached object for the given key

getOrSetDefault

public final <T> T getOrSetDefault(String key,
                                   T defaultValue)

Description copied from interface: Cache

Fetch cached object for a given key or set a non-expiring default value.

If the cache has a non-expired object for the given key, it is returned.

Otherwise, the given default value is set in the cache and returned.

Specified by:

getOrSetDefault in interface Cache

Type Parameters:

T - Object Type

Parameters:

key - Cache Key

defaultValue - Default Value

Returns:

The existing cached object for the given key, or the given default value, never return null

getOrSetDefault

public final <T> T getOrSetDefault(String key,
                                   Supplier<T> defaultValueSupplier)

Description copied from interface: Cache

Fetch cached object for a given key or set a non-expiring default value.

If the cache has a non-expired object for the given key, it is returned.

Otherwise, the given default value is set in the cache and returned.

Specified by:

getOrSetDefault in interface Cache

Type Parameters:

T - Object Type

Parameters:

key - Cache Key

defaultValueSupplier - Default Value Supplier

Returns:

The existing cached object for the given key, or the given default value, never return null

getOrSetDefault

public final <T> T getOrSetDefault(String key,
                                   int ttlSeconds,
                                   T defaultValue)

Description copied from interface: Cache

Fetch cached object for a given key or set an expiring default value.

If the cache has a non-expired object for the given key, it is returned.

Otherwise, the given default value is set in the cache and returned.

Specified by:

getOrSetDefault in interface Cache

Type Parameters:

T - Object Type

Parameters:

key - Cache Key

ttlSeconds - Default Value Time To Live in seconds. If 0 (ZERO), then the entry will never expire

defaultValue - Default Value

Returns:

The existing cached object for the given key, or the given default value, never return null

getOrSetDefault

public final <T> T getOrSetDefault(String key,
                                   int ttlSeconds,
                                   Supplier<T> defaultValueSupplier)

Description copied from interface: Cache

Fetch cached object for a given key or set an expiring default value.

If the cache has a non-expired object for the given key, it is returned.

Otherwise, the given default value is set in the cache and returned.

Specified by:

getOrSetDefault in interface Cache

Type Parameters:

T - Object Type

Parameters:

key - Cache Key

ttlSeconds - Default Value Time To Live in seconds. If 0 (ZERO), then the entry will never expire

defaultValueSupplier - Default Value Supplier

Returns:

The existing cached object for the given key, or the given default value, never return null

set

public final <T> void set(String key,
                          T value)

Description copied from interface: Cache

Set a non-expiring object for a given key in the Cache.

Specified by:

set in interface Cache

Type Parameters:

T - Object Type

Parameters:

key - Cache Key

value - Value Object

set

public final <T> void set(int ttlSeconds,
                          String key,
                          T value)

Description copied from interface: Cache

Set an expiring object for a given key in the Cache.

Specified by:

set in interface Cache

Type Parameters:

T - Object Type

Parameters:

ttlSeconds - Time To Live in seconds. If 0 (ZERO), then the entry will not expire

key - Cache Key

value - Value Object

remove

public final void remove(String key)

Description copied from interface: Cache

Remove a Cache entry.

Specified by:

remove in interface Cache

Parameters:

key - Key of the entry to remove

doGet

protected abstract <T> T doGet(String key)

Concrete GET.

Type Parameters:

T - Parameterized type of value

Parameters:

key - Cache Key

Returns:

Value or null

doSet

protected abstract <T> void doSet(int ttlSeconds,
                                  String key,
                                  T value)

Concrete SET.

Type Parameters:

T - Parameterized type of value

Parameters:

ttlSeconds - TTL in seconds

key - Cache Key

value - Value

doRemove

protected abstract void doRemove(String key)

Concrete REMOVE.

Parameters:

key - Cache Key