类 ConcurrentMapCache

构造器详细资料

• ConcurrentMapCache

  public ConcurrentMapCache​(String name)

  Create a new ConcurrentMapCache with the specified name.

  参数:

  name - the name of the cache

• ConcurrentMapCache

  public ConcurrentMapCache​(String name,
                            boolean allowNullValues)

  Create a new ConcurrentMapCache with the specified name.

  参数:

  name - the name of the cache

  allowNullValues - whether to accept and convert null values for this cache

• ConcurrentMapCache

  public ConcurrentMapCache​(String name,
                            ConcurrentMap<Object,​Object> store,
                            boolean allowNullValues)

  Create a new ConcurrentMapCache with the specified name and the given internal ConcurrentMap to use.

  参数:

  name - the name of the cache

  store - the ConcurrentMap to use as an internal store

  allowNullValues - whether to allow null values (adapting them to an internal null holder value)

• ConcurrentMapCache

  protected ConcurrentMapCache​(String name,
                               ConcurrentMap<Object,​Object> store,
                               boolean allowNullValues,
                               SerializationDelegate serialization)

  Create a new ConcurrentMapCache with the specified name and the given internal ConcurrentMap to use. If the SerializationDelegate is specified, store-by-value is enabled

  参数:

  name - the name of the cache

  store - the ConcurrentMap to use as an internal store

  allowNullValues - whether to allow null values (adapting them to an internal null holder value)

  serialization - the SerializationDelegate to use to serialize cache entry or null to store the reference

  从以下版本开始:

  4.3

方法详细资料

• isStoreByValue

  public final boolean isStoreByValue()

  Return whether this cache stores a copy of each entry (true) or a reference (false, default). If store by value is enabled, each entry in the cache must be serializable.

  从以下版本开始:

  4.3

• getName

  public final String getName()

  从接口复制的说明: Cache
  Return the cache name.

• getNativeCache

  public final ConcurrentMap<Object,​Object> getNativeCache()

  从接口复制的说明: Cache
  Return the underlying native cache provider.

• lookup

  protected Object lookup​(Object key)

  从类复制的说明: AbstractValueAdaptingCache
  Perform an actual lookup in the underlying store.

  指定者:

  lookup 在类中 AbstractValueAdaptingCache

  参数:

  key - the key whose associated value is to be returned

  返回:

  the raw store value for the key, or null if none

• get

  public <T> T get​(Object key,
                   Callable<T> valueLoader)

  从接口复制的说明: Cache
  Return the value to which this cache maps the specified key, obtaining that value from valueLoader if necessary. This method provides a simple substitute for the conventional "if cached, return; otherwise create, cache and return" pattern.

  If possible, implementations should ensure that the loading operation is synchronized so that the specified valueLoader is only called once in case of concurrent access on the same key.

  If the valueLoader throws an exception, it is wrapped in a Cache.ValueRetrievalException

  参数:

  key - the key whose associated value is to be returned

  返回:

  the value to which this cache maps the specified key

• put

  public void put​(Object key,
                  Object value)

  从接口复制的说明: Cache
  Associate the specified value with the specified key in this cache.

  If the cache previously contained a mapping for this key, the old value is replaced by the specified value.

  参数:

  key - the key with which the specified value is to be associated

  value - the value to be associated with the specified key

• putIfAbsent

  public Cache.ValueWrapper putIfAbsent​(Object key,
                                        Object value)

  从接口复制的说明: Cache
  Atomically associate the specified value with the specified key in this cache if it is not set already.

  This is equivalent to:

  
   Object existingValue = cache.get(key);
   if (existingValue == null) {
       cache.put(key, value);
       return null;
   } else {
       return existingValue;
   }
   

  except that the action is performed atomically. While all out-of-the-box CacheManager implementations are able to perform the put atomically, the operation may also be implemented in two steps, e.g. with a check for presence and a subsequent put, in a non-atomic way. Check the documentation of the native cache implementation that you are using for more details.

  参数:

  key - the key with which the specified value is to be associated

  value - the value to be associated with the specified key

  返回:

  the value to which this cache maps the specified key (which may be null itself), or also null if the cache did not contain any mapping for that key prior to this call. Returning null is therefore an indicator that the given value has been associated with the key.

• evict

  public void evict​(Object key)

  从接口复制的说明: Cache
  Evict the mapping for this key from this cache if it is present.

  参数:

  key - the key whose mapping is to be removed from the cache

• clear

  public void clear()

  从接口复制的说明: Cache
  Remove all mappings from the cache.

• toStoreValue

  protected Object toStoreValue​(Object userValue)

  从类复制的说明: AbstractValueAdaptingCache
  Convert the given user value, as passed into the put method, to a value in the internal store (adapting null).

  覆盖:

  toStoreValue 在类中 AbstractValueAdaptingCache

  参数:

  userValue - the given user value

  返回:

  the value to store

• fromStoreValue

  protected Object fromStoreValue​(Object storeValue)

  从类复制的说明: AbstractValueAdaptingCache
  Convert the given value from the internal store to a user value returned from the get method (adapting null).

  覆盖:

  fromStoreValue 在类中 AbstractValueAdaptingCache

  参数:

  storeValue - the store value

  返回:

  the value to return to the user