com.scaleoutsoftware.soss.client.map

Class NamedMap<K,V>

java.lang.Object

com.scaleoutsoftware.soss.client.map.NamedMap<K,V>

Type Parameters:

K - key type

V - value type

All Implemented Interfaces:

ConcurrentMap<K,V>, Map<K,V>

public abstract class NamedMap<K,V>
extends Object
implements ConcurrentMap<K,V>

An implementation of the ConcurrentMap which uses ScaleOut StateServer to store keys and values. The map contents are coherent across the in-memory data grid.

The NamedMap class allows you to efficiently store large numbers of keys and values (typically millions) in the distributed in-memory data grid in such a way that they can be analyzed in bulk very efficiently.

Features:

Loading the NamedMap

To efficiently put or remove a large number of keys, use a BulkLoader view of the map which can be obtained by calling the getBulkLoader() method. This way, multiple map operations are combined into chunks which provides higher overall bandwidth. putAll(java.util.Map) will provide the same performance gain if the keys and values are precomputed and put into an intermediate map.

Client cache

To maximize access performance, the NamedMap maintains an internal client-side cache that contains deserialized versions of the most recently accessed objects. When reading objects, the client-side cache reduces access response time by eliminating data motion and deserialization overhead.

A configurable number of recently accessed values can be stored in the client application's memory using the client-side cache. On subsequent reads, cached values for keys are returned if they are not older than what is allowed by a configurable coherency interval (NamedMap.setCoherencyIntervalMilliseconds(int)). A coherency interval of 0 disables the client-side cache and causes read operations to directly access the StateServer service.

The client-side cache size can be configured by calling the setClientCacheSize(int) function with a new value. The default size is 10,000 entries.

If the client cache is enabled, object changes will be visible to all threads using the same NamedMap instance. The client cache is an in-process reference cache, so, if the client cache is enabled, the application may need to make deep copies of objects in the map if the objects will be simultaneously modified by multiple threads. Deep copying the object will prevent the client-side cache from being corrupted.

By default, the client cache is turned off (coherency interval is 0).

Parallel Method Invocation (PMI)

The ScaleOut StateServer service hosts a powerful parallel execution engine that allows you to efficiently analyze all of the objects in a NamedMap by utilizing all of the hosts in your data grid. Each host simultaneously performs parallel operations on its local subset of keys and values, which boosts performance by avoiding the movement of data across the network. An invocation is initiated by calling the invoke(NamedMapInvokable, Object).

Prior to calling the Invoke method, a Parallel Method Invocation (PMI) operation must be defined by subclassing the NamedMapInvokable. PMI calls require an invocation grid (InvocationGrid) to be assigned to the named map via setInvocationGrid(com.scaleoutsoftware.soss.client.InvocationGrid)

Queries

Queries are parallel operations which run simultaneously on all hosts in the data grid and return a list of matching keys. To query a map, use executeParallelQuery(com.scaleoutsoftware.soss.client.map.QueryCondition) with a QueryCondition implementation as a parameter. If this query condition argument is null then all of the map's keys will be returned.

Query operations require an invocation grid (InvocationGrid) to be assigned to the named map via setInvocationGrid(com.scaleoutsoftware.soss.client.InvocationGrid)

Custom serialization

Custom serialization can be used to efficiently store keys and values in memory. To use a custom serializer, the user must subclass CustomSerializer and implement the serialize and deserialize methods. The custom serializer class can then be provided to the NamedMap factory method: NamedMapFactory.getMap(String, com.scaleoutsoftware.soss.client.CustomSerializer, com.scaleoutsoftware.soss.client.CustomSerializer).

Each instance of the client application across the grid should have the same custom serializers assigned to the map to prevent serialization exceptions.

For Parallel Method Invocation (PMI) operations, if a PMI parameter or result object requires custom serialization, then it can be set by implementing the NamedMapInvokable.getParameterCustomSerializer() and/or NamedMapInvokable.getResultCustomSerializer() methods.

Usage Notes

• Key equality is determined by byte-wise comparison of the serialized representation of the two keys, not by the Object.equals(Object) method of the objects.
• All values returned by map methods are application-local clone objects (i.e., changes made to this value do not affect the globally available value stored in the map until the map is updated by a put operation). If the client cache is enabled, object changes will be visible to all threads using the same cached object (i.e., the client cache is a reference cache). For that reason, if the client cache is enabled, the application should make deep copies of the values before making modifications to avoid race conditions.
• By default, put(Object, Object) and remove(Object) always return null in this implementation to optimize performance by reducing the number of calls to the ScaleOut StateServer service. These methods can be configured to return the previous value by setting the setReturnBehavior(ReturnBehavior) property to ReturnBehavior.STANDARD.
• entrySet() and values() are not supported by this implementation because they require moving all map data to one host, which is extremely inefficient in a distributed environment.
• containsValue(Object) requires an invocation grid (InvocationGrid) to be specified for the map(setInvocationGrid(com.scaleoutsoftware.soss.client.InvocationGrid)).
• Care should be taken when using keySet(), because it requires moving all key data to the calling host, leading to higher memory and network utilization.

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Constructor Summary

Constructors

Constructor and Description
NamedMap()

Method Summary

Modifier and Type	Method and Description
abstract void	clear() Removes all entries from the map.
abstract boolean	containsKey(Object key) Returns true if this map contains a mapping for the specified key.
abstract boolean	containsValue(Object value) Returns true if this map contains one or more keys which map to the specified value.
abstract Set<Map.Entry<K,V>>	entrySet() This implementation does not support this method.
abstract Iterable<K>	executeParallelQuery(QueryCondition<K,V> condition) Runs a parallel query on the map contents with the specified QueryCondition.
abstract Iterable<K>	executeParallelQuery(QueryCondition<K,V> condition, long timeout, TimeUnit unit) Runs a parallel query on the map contents with specified QueryCondition.
abstract V	get(Object key) Returns the value mapped by the specified key, or null if this map contains no mapping for the key.
abstract AvailabilityMode	getAvailabilityMode() Gets whether object replication is enabled for the named map.
abstract BulkLoader<K,V>	getBulkLoader() Gets the BulkLoader view of the NamedMap which can be used to efficiently put a large number of keys in the map.
abstract int	getCoherencyIntervalMilliseconds() Returns the coherency interval in milliseconds.
abstract InvocationGrid	getInvocationGrid() Gets the currently assigned InvocationGrid.
abstract CustomSerializer<K>	getKeySerializer() Gets the CustomSerializer used to serialize and deserialize keys.
abstract Iterable<K>	getKeysForValue(V value) Searches for a specific value in the map and returns all the keys this value is associated with.
abstract int	getMapId() Gets the map ID.
abstract String	getMapName() Gets the map name.
abstract int	getMaxServerRetries() Returns the number of server retries when a race condition between client requests occurs.
abstract ReturnBehavior	getReturnBehavior() Gets the return behavior setting for put(Object, Object) and remove(Object) methods.
com.scaleoutsoftware.soss.client.util.SerializationMode	getSerializationMode()
abstract CustomSerializer<V>	getValueSerializer() Gets the CustomSerializer used to serialize and deserialize values.
abstract boolean	insert(K key, V value) Inserts the key and value into the map if the key does not already exist in the map.
abstract <RESULT,PARAMETER> RESULT	invoke(NamedMapInvokable<K,V,PARAMETER,RESULT> invokable, PARAMETER parameter) Runs a parallel method invocation (NamedMapInvokable) on the map contents and returns the result.
abstract <RESULT,PARAMETER> RESULT	invoke(NamedMapInvokable<K,V,PARAMETER,RESULT> invokable, PARAMETER parameter, long timeout, TimeUnit unit) Runs a parallel method invocation (NamedMapInvokable) on the map contents and returns the result.
abstract boolean	isEmpty() Returns true if this map contains no key-value mappings.
abstract Set<K>	keySet() Returns the set of keys in the map.
abstract V	put(K key, V value) Associates the specified value with the specified key in this map.
abstract void	putAll(Map<? extends K,? extends V> map) Efficiently puts contents of the specified map into the named map.
abstract V	putIfAbsent(K key, V value) Puts the value in the map if the key is absent, otherwise returns the existing value.
abstract V	remove(Object key) Removes the mapping for a key from this map if it is present.
abstract boolean	remove(Object key, Object expectedValue) Removes the entry from the map only if currently mapped to a given value.
abstract V	replace(K key, V value) Replaces the entry for a key only if currently mapped to a value.
abstract boolean	replace(K key, V oldValue, V newValue) Replaces the entry for a key only if currently mapped to a given value.
abstract void	setAvailabilityMode(AvailabilityMode availabilityMode) Sets the @link {AvailabilityMode} which controls whether the in-memory data grid should create object replicas of the named map contents on multiple hosts.
abstract void	setClientCacheSize(int cacheSize) Sets the maximum number of entries (i.e., key-value mappings) in the client cache.
abstract void	setCoherencyIntervalMilliseconds(int coherencyIntervalMilliseconds) Sets the coherency interval, i.e., the maximum allowed time between the last server read request and a get(Object) request before the client will retrieve the object from the server instead of the client cache (if present).
abstract void	setInvocationGrid(InvocationGrid invocationGrid) Assigns the InvocationGrid to the map.
abstract void	setMaxServerRetries(int maxServerRetries) Sets the maximum number of server request retries when a race condition between client requests occur.
abstract void	setReturnBehavior(ReturnBehavior behavior) Sets whether put(Object, Object) and remove(Object) methods should return the previous value associated with the key.
void	setSerializationMode(com.scaleoutsoftware.soss.client.util.SerializationMode sm) Set the serialization mode.
abstract int	size() Returns the number of key-value mappings in this map.
abstract boolean	update(K key, V value) Updates the key with the new value if the key already exists in the map.
abstract Collection<V>	values() This implementation does not support this method.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.concurrent.ConcurrentMap

compute, computeIfAbsent, computeIfPresent, forEach, getOrDefault, merge, replaceAll

Methods inherited from interface java.util.Map

equals, hashCode

Constructor Detail

NamedMap

public NamedMap()

Method Detail

putIfAbsent

public abstract V putIfAbsent(K key,
                              V value)

Puts the value in the map if the key is absent, otherwise returns the existing value.

Note: if the previous value is not required, use insert(Object, Object) for better performance.

Specified by:

putIfAbsent in interface ConcurrentMap<K,V>

Specified by:

putIfAbsent in interface Map<K,V>

Parameters:

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

value - value to be associated with the specified key

Returns:

the previous value associated with the specified key, or null if there was no mapping for the key.

Throws:

NullPointerException - if the specified key or value is null

RuntimeException - if a communication error occurred

remove

public abstract boolean remove(Object key,
                               Object expectedValue)

Removes the entry from the map only if currently mapped to a given value.

Specified by:

remove in interface ConcurrentMap<K,V>

Specified by:

remove in interface Map<K,V>

Parameters:

key - key with which the specified value is associated

expectedValue - value expected to be associated with the specified key

Returns:

true if the value was removed

Throws:

NullPointerException - if the specified key or value is null

RuntimeException - if a communication error occurred

replace

public abstract boolean replace(K key,
                                V oldValue,
                                V newValue)

Replaces the entry for a key only if currently mapped to a given value.

Specified by:

replace in interface ConcurrentMap<K,V>

Specified by:

replace in interface Map<K,V>

Parameters:

key - key with which the specified value is associated

oldValue - value expected to be associated with the specified key

newValue - value to be associated with the specified key

Returns:

true if the value was replaced

Throws:

NullPointerException - if the specified key or value is null

RuntimeException - if a communication error occurred

replace

public abstract V replace(K key,
                          V value)

Replaces the entry for a key only if currently mapped to a value.

Specified by:

replace in interface ConcurrentMap<K,V>

Specified by:

replace in interface Map<K,V>

Parameters:

key - key with which the specified value is associated

value - value to be associated with the specified key

Returns:

the previous value associated with the specified key, or null if there was no mapping for the key.

Throws:

NullPointerException - if the specified key or value is null

RuntimeException - if a communication error occurred

containsKey

public abstract boolean containsKey(Object key)

Returns true if this map contains a mapping for the specified key.

Note: keys are compared by a byte-wise comparison of their serialized representations, not by Object.equals(Object).

Specified by:

containsKey in interface Map<K,V>

Parameters:

key - key whose presence in this map is to be tested

Returns:

true if this map contains a mapping for the specified key

Throws:

NullPointerException - if the specified key is null

RuntimeException - if a communication error occurred

get

public abstract V get(Object key)

Returns the value mapped by the specified key, or null if this map contains no mapping for the key.

The returned value is an application-local clone object (i.e., changes made to this value do not affect the globally available value stored in the map until the map is updated by a put operation). If the client cache is enabled, object changes will be visible to all threads using the same cached object (i.e., the client cache is a reference cache). For that reason, if the client cache is enabled, the application should make a deep copy of the value before making modifications to avoid race conditions.

If the client cache size(setClientCacheSize(int)) and coherency interval(setCoherencyIntervalMilliseconds(int)) are greater than zero, client cached value may be returned if it is not older than the coherency interval.

Specified by:

get in interface Map<K,V>

Parameters:

key - the key whose associated value is to be returned

Returns:

the value to which the specified key is mapped, or null if this map contains no mapping for the key

Throws:

NullPointerException - if the specified key is null

RuntimeException - if a communication error occurred

put

public abstract V put(K key,
                      V value)

Associates the specified value with the specified key in this map. If the map previously contained a mapping for the key, the old value is replaced by the specified value.

Note: For optimal performance, this implementation this method always returns null by default. To return the previous value, set setReturnBehavior(ReturnBehavior) to ReturnBehavior.STANDARD.

Specified by:

put in interface Map<K,V>

Parameters:

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

value - value to be associated with the specified key

Returns:

the previous value associated with key, or null if there was no mapping for key or setReturnBehavior(ReturnBehavior) is set to ReturnBehavior.RETURN_NULL.

Throws:

NullPointerException - if the specified key or value is null

RuntimeException - if a communication error occurred

remove

public abstract V remove(Object key)

Removes the mapping for a key from this map if it is present.

Note: For optimal performance, this implementation this method always returns null by default. To return the previous value, set setReturnBehavior(ReturnBehavior) to ReturnBehavior.STANDARD.

Specified by:

remove in interface Map<K,V>

Parameters:

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

Returns:

the previous value associated with key, or null if there was no mapping for key or setReturnBehavior(ReturnBehavior) is set to ReturnBehavior.RETURN_NULL.

Throws:

NullPointerException - if the specified key is null

RuntimeException - if a communication error occurred

clear

public abstract void clear()

Removes all entries from the map.

Specified by:

clear in interface Map<K,V>

Throws:

RuntimeException - if a communication error occurred

insert

public abstract boolean insert(K key,
                               V value)

Inserts the key and value into the map if the key does not already exist in the map.

Parameters:

key - key to insert

value - value for the key

Returns:

true if insert succeeded, false if the key already exists in the map

Throws:

RuntimeException - if a communication error occurred

update

public abstract boolean update(K key,
                               V value)

Updates the key with the new value if the key already exists in the map.

Parameters:

key - key to update

value - new value for the key

Returns:

true if update succeeded, false if the key is absent in the map

Throws:

RuntimeException - if a communication error occurred

putAll

public abstract void putAll(Map<? extends K,? extends V> map)

Efficiently puts contents of the specified map into the named map. This method should be preferred to put(Object, Object) when updating the map with a large number of keys and values. If the named map already contains a mapping for a key, its value will be replaced with the value in the input map.

Specified by:

putAll in interface Map<K,V>

Parameters:

map - map containing keys and values to be put into the named map

Throws:

RuntimeException - if a communication error occurred

keySet

public abstract Set<K> keySet()

Returns the set of keys in the map.

This method should be used with caution since it requires copying all map keys to a single host. Parallel method invocations(invoke(NamedMapInvokable, Object)) are the preferred way to iterate through map contents if the size of the map is significant.

Specified by:

keySet in interface Map<K,V>

Returns:

Set containing all the keys in the map

Throws:

RuntimeException - if a communication error occurred

values

public abstract Collection<V> values()

This implementation does not support this method.

Specified by:

values in interface Map<K,V>

Throws:

UnsupportedOperationException - this operation is not supported

entrySet

public abstract Set<Map.Entry<K,V>> entrySet()

This implementation does not support this method.

Specified by:

entrySet in interface Map<K,V>

Throws:

UnsupportedOperationException - this operation is not supported

size

public abstract int size()

Returns the number of key-value mappings in this map.

Specified by:

size in interface Map<K,V>

Returns:

the number of key-value mappings in this map

Throws:

RuntimeException - when a communication error occurred

isEmpty

public abstract boolean isEmpty()

Returns true if this map contains no key-value mappings.

Specified by:

isEmpty in interface Map<K,V>

Returns:

true if this map contains no key-value mappings

Throws:

RuntimeException - if a communication error occurred

getInvocationGrid

public abstract InvocationGrid getInvocationGrid()

Gets the currently assigned InvocationGrid.

Returns:

currently assigned invocation grid, or null if none

setInvocationGrid

public abstract void setInvocationGrid(InvocationGrid invocationGrid)

Assigns the InvocationGrid to the map. The invocation grid is used to perform queries and parallel invocations across all nodes in the data grid. To construct an invocation grid, use InvocationGridBuilder.

Parameters:

invocationGrid - invocation grid to assign to this map

invoke

public abstract <RESULT,PARAMETER> RESULT invoke(NamedMapInvokable<K,V,PARAMETER,RESULT> invokable,
                                                 PARAMETER parameter)
                                          throws InvokeException

Runs a parallel method invocation (NamedMapInvokable) on the map contents and returns the result.

Note: This method requires that an invocation grid is assigned to this map (setInvocationGrid(com.scaleoutsoftware.soss.client.InvocationGrid)).

Type Parameters:

RESULT - result type

PARAMETER - invocation parameter type

Parameters:

invokable - parallel operation to run.

parameter - invocation parameter

Returns:

invocation result

Throws:

InvokeException - if exception occurred during parallel method invocation

RuntimeException - if a communication error occurred

invoke

public abstract <RESULT,PARAMETER> RESULT invoke(NamedMapInvokable<K,V,PARAMETER,RESULT> invokable,
                                                 PARAMETER parameter,
                                                 long timeout,
                                                 TimeUnit unit)
                                          throws InvokeException

Runs a parallel method invocation (NamedMapInvokable) on the map contents and returns the result.

Note: This method requires that an invocation grid is assigned to this map (setInvocationGrid(com.scaleoutsoftware.soss.client.InvocationGrid)).

Type Parameters:

RESULT - result type

PARAMETER - invocation parameter type

Parameters:

invokable - parallel operation to run.

parameter - invocation parameter

timeout - invocation timeout

unit - time unit for invocation timeout

Returns:

invocation result

Throws:

InvokeException - if exception occurred during parallel method invocation

RuntimeException - if a communication error occurred

executeParallelQuery

public abstract Iterable<K> executeParallelQuery(QueryCondition<K,V> condition)
                                          throws InvokeException

Runs a parallel query on the map contents with the specified QueryCondition.

Note: This method requires that an invocation grid is assigned to this map (setInvocationGrid(com.scaleoutsoftware.soss.client.InvocationGrid)).

Parameters:

condition - condition used to select entries

Returns:

Iterable collection of all matching keys

Throws:

InvokeException - if exception occurred during parallel operation

RuntimeException - if a communication error occurred

executeParallelQuery

public abstract Iterable<K> executeParallelQuery(QueryCondition<K,V> condition,
                                                 long timeout,
                                                 TimeUnit unit)
                                          throws InvokeException

Runs a parallel query on the map contents with specified QueryCondition.

Note: This method requires that an invocation grid is assigned to this map (setInvocationGrid(com.scaleoutsoftware.soss.client.InvocationGrid)).

Parameters:

condition - condition used to select entries

timeout - maximum query run time

unit - time units for the query timeout

Returns:

Iterable collection of all matching keys

Throws:

InvokeException - if exception occurred during parallel operation

RuntimeException - if a communication error occurred

getKeysForValue

public abstract Iterable<K> getKeysForValue(V value)
                                     throws InvokeException

Searches for a specific value in the map and returns all the keys this value is associated with.

Note: This method requires that an invocation grid is assigned to this map (setInvocationGrid(com.scaleoutsoftware.soss.client.InvocationGrid)).

Parameters:

value - value to search for in the map

Returns:

Iterable collection of all keys which the provided value is associated with

Throws:

NullPointerException - if the specified value is null

InvokeException - if exception occurred during parallel operation

RuntimeException - if a communication error occurred

containsValue

public abstract boolean containsValue(Object value)

Returns true if this map contains one or more keys which map to the specified value.

Note: This method requires that an invocation grid is assigned to this map (setInvocationGrid(com.scaleoutsoftware.soss.client.InvocationGrid)).

Specified by:

containsValue in interface Map<K,V>

Parameters:

value - value whose presence in this map is to be tested

Returns:

true if this map contains one or more keys which map to the specified value, otherwise false

Throws:

NullPointerException - if the specified value is null

RuntimeException - if a communication error occurred

getBulkLoader

public abstract BulkLoader<K,V> getBulkLoader()

Gets the BulkLoader view of the NamedMap which can be used to efficiently put a large number of keys in the map.

Returns:

BulkLoader instance

getReturnBehavior

public abstract ReturnBehavior getReturnBehavior()

Gets the return behavior setting for put(Object, Object) and remove(Object) methods.

Returns:

the ReturnBehavior setting

setReturnBehavior

public abstract void setReturnBehavior(ReturnBehavior behavior)

Sets whether put(Object, Object) and remove(Object) methods should return the previous value associated with the key.

Parameters:

behavior - the return behavior

getMaxServerRetries

public abstract int getMaxServerRetries()

Returns the number of server retries when a race condition between client requests occurs.

The maxServerRetries property is used when server requests lose a race with another server request that attempts to modify the same object. This race condition can occur in the put and putIfAbsent methods, and both the remove methods. The number of server request retries in these methods are limited by this property, and a RuntimeException is thrown if the race is not resolved after that number of retries. maxServerRetries is set to a reasonable default value of 1000 retries, and under normal operation does not need to be changed.

Returns:

number of server retries when a race condition between client requests occurs

setMaxServerRetries

public abstract void setMaxServerRetries(int maxServerRetries)

Sets the maximum number of server request retries when a race condition between client requests occur.

The maxServerRetries property is used when server requests lose a race with another server request that attempts to modify the same object. This race condition can occur in the put and putIfAbsent methods, and both the remove methods. The number of server request retries in these methods are limited by this property, and a RuntimeException is thrown if the race is not resolved after that number of retries. maxServerRetries is set to a reasonable default value of 1000 retries, and under normal operation does not need to be changed.

maxServerRetries can be increased to a bigger value (e.g. 10000) in case of larger number of concurrent threads accessing the object, to allow race conditions to be successfully resolved.

Parameters:

maxServerRetries - the number of server retries

getCoherencyIntervalMilliseconds

public abstract int getCoherencyIntervalMilliseconds()

Returns the coherency interval in milliseconds.

Returns:

coherency interval in milliseconds

setCoherencyIntervalMilliseconds

public abstract void setCoherencyIntervalMilliseconds(int coherencyIntervalMilliseconds)

Sets the coherency interval, i.e., the maximum allowed time between the last server read request and a get(Object) request before the client will retrieve the object from the server instead of the client cache (if present). A coherency interval of 0 means that the values are never served out of the client cache. Coherency interval is set to 0 by default, so get(Object) always retrieves latest value from the server.

Parameters:

coherencyIntervalMilliseconds - coherency interval in milliseconds

setClientCacheSize

public abstract void setClientCacheSize(int cacheSize)

Sets the maximum number of entries (i.e., key-value mappings) in the client cache. Client cache size is set to 10000 by default.

Parameters:

cacheSize - number of entries (i.e., key-value mappings) in the client cache

getKeySerializer

public abstract CustomSerializer<K> getKeySerializer()

Gets the CustomSerializer used to serialize and deserialize keys.

Custom serializers can be assigned to the NamedMap with NamedMapFactory.getMap(String, com.scaleoutsoftware.soss.client.CustomSerializer, com.scaleoutsoftware.soss.client.CustomSerializer).

Returns:

custom key serializer

getValueSerializer

public abstract CustomSerializer<V> getValueSerializer()

Gets the CustomSerializer used to serialize and deserialize values.

Custom serializers can be assigned to the NamedMap with NamedMapFactory.getMap(String, com.scaleoutsoftware.soss.client.CustomSerializer, com.scaleoutsoftware.soss.client.CustomSerializer).

Returns:

custom value serializer

getAvailabilityMode

public abstract AvailabilityMode getAvailabilityMode()

Gets whether object replication is enabled for the named map.

Enabling object replication provides fault tolerance, i.e., it ensures that no data is lost in case of host failure at the expense of increased memory and network utilization. If replication is enabled, the number of replicas created is controlled by the max_replicas parameter in the ScaleOut StateServer configuration file (soss_params.txt).

Returns:

true if replication is enabled, false otherwise

setAvailabilityMode

public abstract void setAvailabilityMode(AvailabilityMode availabilityMode)

Sets the @link {AvailabilityMode} which controls whether the in-memory data grid should create object replicas of the named map contents on multiple hosts.

Enabling object replication provides fault tolerance, i.e., it ensures that no data is lost in case of host failure at the expense of increased memory and network utilization. If replication is enabled, the number of replicas created is controlled by the max_replicas parameter in the ScaleOut StateServer configuration.

By default, replication is enabled.

Parameters:

availabilityMode - availability mode

getMapId

public abstract int getMapId()

Gets the map ID.

Returns:

map ID

getMapName

public abstract String getMapName()

Gets the map name.

Returns:

map name

setSerializationMode

public void setSerializationMode(com.scaleoutsoftware.soss.client.util.SerializationMode sm)

Set the serialization mode.

getSerializationMode

public com.scaleoutsoftware.soss.client.util.SerializationMode getSerializationMode()