org.infinispan.client.hotrod

Interface RemoteCache<K,V>

public interface RemoteCache<K,V>

Provides remote reference to a Hot Rod server/cluster. It implements Cache, but given its nature (remote) some operations are not supported. All these unsupported operations are being overridden within this interface and documented as such.

New operations: besides the operations inherited from Cache, RemoteCache also adds new operations to optimize/reduce network traffic: e.g. versioned put operation.

Concurrency: implementors of this interface will support multi-threaded access, similar to the way Cache supports it.

Return values: previously existing values for certain Map operations are not returned, null is returned instead. E.g. Map.put(Object, Object) returns the previous value associated to the supplied key. In case of RemoteCache, this returns null.

Synthetic operations: aggregate operations are being implemented based on other Hot Rod operations. E.g. all the Map.putAll(java.util.Map) is implemented through multiple individual puts. This means that the these operations are not atomic and that they are costly, e.g. as the number of network round-trips is not one, but the size of the added map. All these synthetic operations are documented as such.

changing default behavior through Flags: it is possible to change the default cache behaviour by using flags on an per invocation basis. E.g.

      RemoteCache cache = getRemoteCache();
      Object oldValue = cache.withFlags(Flag.FORCE_RETURN_VALUE).put(aKey, aValue);
 

In the previous example, using Flag.FORCE_RETURN_VALUE will make the client to also return previously existing value associated with aKey. If this flag would not be present, Infinispan would return (by default) null. This is in order to avoid fetching a possibly large object from the remote server, which might not be needed. The flags as set by the withFlags(Flag...) operation only apply for the very next operation executed by the same thread on the RemoteCache.

Eviction and expiration: Unlike local Cache cache, which allows specifying time values with any granularity (as defined by TimeUnit), HotRod only supports seconds as time units. If a different time unit is used instead, HotRod will transparently convert it to seconds, using TimeUnit.toSeconds(long) method. This might result in loss of precision for values specified as nanos or milliseconds.
Another fundamental difference is in the case of lifespan (naturally does NOT apply for max idle): If number of seconds is bigger than 30 days, this number of seconds is treated as UNIX time and so, represents the number of seconds since 1/1/1970.
Note on default expiration values: Due to limitations on the first version of the protocol, it's not possible for clients to rely on default lifespan and maxIdle values set on the server. This is because the protocol does not support a way to tell the server that no expiration lifespan and/or maxIdle were provided and that default values should be used. This will be resolved in a future revision of the protocol. In the mean time, the workaround is to explicitly provide the desired expiry lifespan/maxIdle values in each remote cache operation.

Since:

4.1

Author:

Mircea.Markus@jboss.com

Method Summary

Methods

Modifier and Type	Method and Description
boolean	containsValue(java.lang.Object value)
java.util.Set<>	entrySet()
java.util.Map<K,V>	getBulk() Bulk get operations, returns all the entries within the remote cache.
java.util.Map<K,V>	getBulk(int size) Same as getBulk(), but limits the returned set of values to the specified size.
java.lang.String	getProtocolVersion() Returns the HotRod protocol version supported by this RemoteCache implementation
RemoteCacheManager	getRemoteCacheManager() Returns the RemoteCacheManager that created this cache.
VersionedValue<V>	getVersioned(K key) Returns the VersionedValue associated to the supplied key param, or null if it doesn't exist.
MetadataValue<V>	getWithMetadata(K key) Returns the MetadataValue associated to the supplied key param, or null if it doesn't exist.
boolean	isEmpty()
java.util.Set<K>	keySet() Returns all keys in the remote server.
void	putAll(java.util.Map<? extends K,? extends V> m) Synthetic operation.
void	putAll(java.util.Map<? extends K,? extends V> map, long lifespan, java.util.concurrent.TimeUnit unit) Synthetic operation.
void	putAll(java.util.Map<? extends K,? extends V> map, long lifespan, java.util.concurrent.TimeUnit lifespanUnit, long maxIdleTime, java.util.concurrent.TimeUnit maxIdleTimeUnit) Synthetic operation.
	putAllAsync(java.util.Map<? extends K,? extends V> data) Synthetic operation.
	putAllAsync(java.util.Map<? extends K,? extends V> data, long lifespan, java.util.concurrent.TimeUnit unit) Synthetic operation.
	putAllAsync(java.util.Map<? extends K,? extends V> data, long lifespan, java.util.concurrent.TimeUnit lifespanUnit, long maxIdle, java.util.concurrent.TimeUnit maxIdleUnit) Synthetic operation.
boolean	removeWithVersion(K key, long version) Removes the given entry only if its version matches the supplied version.
	removeWithVersionAsync(K key, long version)
boolean	replaceWithVersion(K key, V newValue, long version) Replaces the given value only if its version matches the supplied version.
boolean	replaceWithVersion(K key, V newValue, long version, int lifespanSeconds) A overloaded form of replaceWithVersion(Object, Object, long) which takes in lifespan parameters.
boolean	replaceWithVersion(K key, V newValue, long version, int lifespanSeconds, int maxIdleTimeSeconds) A overloaded form of replaceWithVersion(Object, Object, long) which takes in lifespan and maximum idle time parameters.
	replaceWithVersionAsync(K key, V newValue, long version)
	replaceWithVersionAsync(K key, V newValue, long version, int lifespanSeconds)
	replaceWithVersionAsync(K key, V newValue, long version, int lifespanSeconds, int maxIdleSeconds)
int	size()
ServerStatistics	stats()
java.util.Collection<V>	values()
RemoteCache<K,V>	withFlags(Flag... flags) Applies one or more Flags to the scope of a single invocation.

Method Detail

removeWithVersion

boolean removeWithVersion(K key,
                        long version)

Removes the given entry only if its version matches the supplied version. A typical use case looks like this:

 VersionedEntry ve = remoteCache.getVersioned(key);
 //some processing
 remoteCache.removeWithVersion(key, ve.getVersion();
 

Lat call (removeWithVersion) will make sure that the entry will only be removed if it hasn't been changed in between.

Returns:

true if the entry has been removed

See Also:

VersionedValue, getVersioned(Object)

removeWithVersionAsync

 removeWithVersionAsync(K key,
                           long version)

See Also:

#remove(Object, Object)

replaceWithVersion

boolean replaceWithVersion(K key,
                         V newValue,
                         long version)

Replaces the given value only if its version matches the supplied version. See removeWithVersion(Object, long) for a sample usage of the version-based methods.

Parameters:

version - numeric version that should match the one in the server for the operation to succeed

Returns:

true if the value has been replaced

See Also:

getVersioned(Object), VersionedValue

replaceWithVersion

boolean replaceWithVersion(K key,
                         V newValue,
                         long version,
                         int lifespanSeconds)

A overloaded form of replaceWithVersion(Object, Object, long) which takes in lifespan parameters.

Parameters:

key - key to use

newValue - new value to be associated with the key

version - numeric version that should match the one in the server for the operation to succeed

lifespanSeconds - lifespan of the entry

Returns:

true if the value was replaced

replaceWithVersion

boolean replaceWithVersion(K key,
                         V newValue,
                         long version,
                         int lifespanSeconds,
                         int maxIdleTimeSeconds)

A overloaded form of replaceWithVersion(Object, Object, long) which takes in lifespan and maximum idle time parameters.

Parameters:

key - key to use

newValue - new value to be associated with the key

version - numeric version that should match the one in the server for the operation to succeed

lifespanSeconds - lifespan of the entry

maxIdleTimeSeconds - the maximum amount of time this key is allowed to be idle for before it is considered as expired

Returns:

true if the value was replaced

replaceWithVersionAsync

 replaceWithVersionAsync(K key,
                            V newValue,
                            long version)

See Also:

replaceWithVersion(Object, Object, long)

replaceWithVersionAsync

 replaceWithVersionAsync(K key,
                            V newValue,
                            long version,
                            int lifespanSeconds)

See Also:

replaceWithVersion(Object, Object, long)

replaceWithVersionAsync

 replaceWithVersionAsync(K key,
                            V newValue,
                            long version,
                            int lifespanSeconds,
                            int maxIdleSeconds)

See Also:

replaceWithVersion(Object, Object, long)

getVersioned

VersionedValue<V> getVersioned(K key)

Returns the VersionedValue associated to the supplied key param, or null if it doesn't exist.

getWithMetadata

MetadataValue<V> getWithMetadata(K key)

Returns the MetadataValue associated to the supplied key param, or null if it doesn't exist.

size

int size()

Throws:

java.lang.UnsupportedOperationException

isEmpty

boolean isEmpty()

Throws:

java.lang.UnsupportedOperationException

containsValue

boolean containsValue(java.lang.Object value)

Throws:

java.lang.UnsupportedOperationException

keySet

java.util.Set<K> keySet()

Returns all keys in the remote server. It'll invoke a command over the network each time this method is called. If the remote cache is a distributed cache, it will retrieve all of the keys from all nodes in the cluster. Please use with care for cache with large data set.

values

java.util.Collection<V> values()

Throws:

java.lang.UnsupportedOperationException

entrySet

java.util.Set<> entrySet()

Throws:

java.lang.UnsupportedOperationException

putAll

void putAll(java.util.Map<? extends K,? extends V> map,
          long lifespan,
          java.util.concurrent.TimeUnit unit)

Synthetic operation. The client iterates over the set of keys and calls put for each one of them. This results in operation not being atomic (if a failure happens after few puts it is not rolled back) and costly (for each key in the parameter map a remote call is performed).

putAll

void putAll(java.util.Map<? extends K,? extends V> map,
          long lifespan,
          java.util.concurrent.TimeUnit lifespanUnit,
          long maxIdleTime,
          java.util.concurrent.TimeUnit maxIdleTimeUnit)

Synthetic operation.

See Also:

putAll(java.util.Map, long, java.util.concurrent.TimeUnit)

putAllAsync

 putAllAsync(java.util.Map<? extends K,? extends V> data)

Synthetic operation.

See Also:

putAll(java.util.Map, long, java.util.concurrent.TimeUnit)

putAllAsync

 putAllAsync(java.util.Map<? extends K,? extends V> data,
                long lifespan,
                java.util.concurrent.TimeUnit unit)

Synthetic operation.

See Also:

putAll(java.util.Map, long, java.util.concurrent.TimeUnit)

putAllAsync

 putAllAsync(java.util.Map<? extends K,? extends V> data,
                long lifespan,
                java.util.concurrent.TimeUnit lifespanUnit,
                long maxIdle,
                java.util.concurrent.TimeUnit maxIdleUnit)

Synthetic operation.

See Also:

putAll(java.util.Map, long, java.util.concurrent.TimeUnit)

putAll

void putAll(java.util.Map<? extends K,? extends V> m)

Synthetic operation.

See Also:

putAll(java.util.Map, long, java.util.concurrent.TimeUnit)

stats

ServerStatistics stats()

withFlags

RemoteCache<K,V> withFlags(Flag... flags)

Applies one or more Flags to the scope of a single invocation. See the Flag enumeration to for information on available flags.

Sample usage:

    remoteCache.withFlags(Flag.FORCE_RETURN_VALUE).put("hello", "world");
 

Parameters:

flags -

Returns:

the current RemoteCache instance to continue running operations on.

getRemoteCacheManager

RemoteCacheManager getRemoteCacheManager()

Returns the RemoteCacheManager that created this cache.

getBulk

java.util.Map<K,V> getBulk()

Bulk get operations, returns all the entries within the remote cache.

Returns:

the returned values depend on the configuration of the back-end infinispan servers. Read this for more details. The returned Map is unmodifiable.

getBulk

java.util.Map<K,V> getBulk(int size)

Same as getBulk(), but limits the returned set of values to the specified size. No ordering is guaranteed, and there is no guarantee that "size" elements are returned( e.g. if the number of elements in the back-end server is smaller that "size")

getProtocolVersion

java.lang.String getProtocolVersion()

Returns the HotRod protocol version supported by this RemoteCache implementation