org.springframework.data.gemfire
Class GemfireTemplate

java.lang.Object
  org.springframework.data.gemfire.GemfireAccessor
      org.springframework.data.gemfire.GemfireTemplate

All Implemented Interfaces:

InitializingBean

public class GemfireTemplate
extends GemfireAccessor

Helper class that simplifies GemFire data access code and converts GemFireCheckedException and GemFireException into Spring DataAccessException, following the org.springframework.dao exception hierarchy.

The central method is execute, supporting GemFire access code implementing the GemfireCallback interface. It provides dedicated handling such that neither the GemfireCallback implementation nor the calling code needs to explicitly care about handling Region life-cycle exceptions. Typically used to implement data access or business logic services that use GemFire within their implementation but are GemFire-agnostic in their interface. The latter or code calling the latter only have to deal with business objects, query objects, and org.springframework.dao exceptions.

Field Summary

Fields inherited from class org.springframework.data.gemfire.GemfireAccessor

log

Constructor Summary

GemfireTemplate()

GemfireTemplate(com.gemstone.gemfire.cache.Region<K,V> region)

Method Summary

void	afterPropertiesSet()
boolean	containsKey(Object key)
boolean	containsKeyOnServer(Object key)
boolean	containsValue(Object value)
boolean	containsValueForKey(Object key)
<K,V> void	create(K key, V value)
protected <K,V> com.gemstone.gemfire.cache.Region<K,V>	createRegionProxy(com.gemstone.gemfire.cache.Region<K,V> region) Create a close-suppressing proxy for the given GemFire Region.
<T> T	execute(GemfireCallback<T> action)
<T> T	execute(GemfireCallback<T> action, boolean exposeNativeRegion) Execute the action specified by the given action object within a Region.
<E> com.gemstone.gemfire.cache.query.SelectResults<E>	find(String query, Object... params) Executes a GemFire query with the given (optional) parameters and returns the result.
<T> T	findUnique(String query, Object... params) Executes a GemFire query with the given (optional) parameters and returns the result.
<K,V> V	get(K key)
<K,V> Map<K,V>	getAll(Collection<?> keys)
boolean	isExposeNativeRegion() Returns whether to expose the native GemFire Region to GemfireCallback code, or rather a Region proxy.
protected com.gemstone.gemfire.cache.query.QueryService	lookupQueryService(com.gemstone.gemfire.cache.Region<?,?> region) Returns the query service used by the template in its find methods.
<K,V> V	put(K key, V value)
<K,V> void	putAll(Map<? extends K,? extends V> map)
<K,V> V	putIfAbsent(K key, V value)
<E> com.gemstone.gemfire.cache.query.SelectResults<E>	query(String query) Shortcut for Region.query(String) method.
<K,V> V	remove(K key)
<K,V> V	replace(K key, V value)
<K,V> boolean	replace(K key, V oldValue, V newValue)
void	setExposeNativeRegion(boolean exposeNativeRegion) Sets whether to expose the native Gemfire Region to GemfireCallback code.

Methods inherited from class org.springframework.data.gemfire.GemfireAccessor

convertGemFireAccessException, convertGemFireAccessException, convertGemFireQueryException, getRegion, setRegion

Methods inherited from class java.lang.Object

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

Constructor Detail

GemfireTemplate

public GemfireTemplate()

GemfireTemplate

public GemfireTemplate(com.gemstone.gemfire.cache.Region<K,V> region)

Method Detail

afterPropertiesSet

public void afterPropertiesSet()

Specified by:

afterPropertiesSet in interface InitializingBean

Overrides:

afterPropertiesSet in class GemfireAccessor

setExposeNativeRegion

public void setExposeNativeRegion(boolean exposeNativeRegion)

Sets whether to expose the native Gemfire Region to GemfireCallback code. Default is "false": a Region proxy will be returned, suppressing close calls.

As there is often a need to cast to a interface, the exposed proxy implements all interfaces implemented by the original Region. If this is not sufficient, turn this flag to "true".

See Also:

GemfireCallback

isExposeNativeRegion

public boolean isExposeNativeRegion()

Returns whether to expose the native GemFire Region to GemfireCallback code, or rather a Region proxy.

containsKey

public boolean containsKey(Object key)

containsKeyOnServer

public boolean containsKeyOnServer(Object key)

containsValue

public boolean containsValue(Object value)

containsValueForKey

public boolean containsValueForKey(Object key)

create

public <K,V> void create(K key,
                         V value)

get

public <K,V> V get(K key)

put

public <K,V> V put(K key,
                   V value)

putIfAbsent

public <K,V> V putIfAbsent(K key,
                           V value)

remove

public <K,V> V remove(K key)

replace

public <K,V> V replace(K key,
                       V value)

replace

public <K,V> boolean replace(K key,
                             V oldValue,
                             V newValue)

getAll

public <K,V> Map<K,V> getAll(Collection<?> keys)

putAll

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

query

public <E> com.gemstone.gemfire.cache.query.SelectResults<E> query(String query)

Shortcut for Region.query(String) method. Filters the values of this region using the predicate given as a string with the syntax of the WHERE clause of the query language. The predefined variable this may be used inside the predicate to denote the current element being filtered. This method evaluates the passed in where clause and returns results. It is supported on servers as well as clients. When executed on a client, this method always runs on the server and returns results. When invoking this method from the client, applications can pass in a where clause or a complete query.

Parameters:

query - A query language boolean query predicate.

Returns:

A SelectResults containing the values of this Region that match the predicate.

See Also:

Region.query(String)

find

public <E> com.gemstone.gemfire.cache.query.SelectResults<E> find(String query,
                                                                  Object... params)
                                                       throws InvalidDataAccessApiUsageException

Executes a GemFire query with the given (optional) parameters and returns the result. Note this method expects the query to return multiple results; for queries that return only one element use findUnique(String, Object...).

As oppose, to the query(String) method, this method allows for more generic queries (against multiple regions even) to be executed.

Note that the local query service is used if the region is configured as a client without any pool configuration or server connectivity - otherwise the query service on the default pool is being used.

Parameters:

query - GemFire query

params - Values that are bound to parameters (such as $1) in this query.

Returns:

A SelectResults instance holding the objects matching the query

Throws:

InvalidDataAccessApiUsageException - in case the query returns a single result (not a SelectResults).

See Also:

QueryService.newQuery(String), Query.execute(Object[]), SelectResults

findUnique

public <T> T findUnique(String query,
                        Object... params)
             throws InvalidDataAccessApiUsageException

Executes a GemFire query with the given (optional) parameters and returns the result. Note this method expects the query to return a single result; for queries that return multiple elements use find(String, Object...).

As oppose, to the query(String) method, this method allows for more generic queries (against multiple regions even) to be executed.

Note that the local query service is used if the region is configured as a client without any pool configuration or server connectivity - otherwise the query service on the default pool is being used.

Parameters:

query - GemFire query

params - Values that are bound to parameters (such as $1) in this query.

Returns:

The (single) object that represents the result of the query.

Throws:

InvalidDataAccessApiUsageException - in case the query returns multiple objects (through SelectResults).

See Also:

QueryService.newQuery(String), Query.execute(Object[])

lookupQueryService

protected com.gemstone.gemfire.cache.query.QueryService lookupQueryService(com.gemstone.gemfire.cache.Region<?,?> region)

Returns the query service used by the template in its find methods.

Parameters:

region - region to find the local query service from

Returns:

query service to use, local or generic

execute

public <T> T execute(GemfireCallback<T> action)
          throws DataAccessException

Throws:

DataAccessException

execute

public <T> T execute(GemfireCallback<T> action,
                     boolean exposeNativeRegion)
          throws DataAccessException

Execute the action specified by the given action object within a Region.

Parameters:

action - callback object that specifies the Gemfire action

exposeNativeRegion - whether to expose the native GemFire region to callback code

Returns:

a result object returned by the action, or null

Throws:

DataAccessException - in case of GemFire errors

createRegionProxy

protected <K,V> com.gemstone.gemfire.cache.Region<K,V> createRegionProxy(com.gemstone.gemfire.cache.Region<K,V> region)

Create a close-suppressing proxy for the given GemFire Region. Called by the execute method.

Parameters:

region - the GemFire Region to create a proxy for

Returns:

the Region proxy, implementing all interfaces implemented by the passed-in Region object

See Also:

Region.close(), execute(GemfireCallback, boolean)