无法使用ehcache配置JPA

Question

I have been trying to configure JPA with ehcache but no success till now. The configurations which i am doing are :

• persistence.xml

   <persistence-unit name="customDatabase"> <jta-data-source>jdbc/oracleXE_DS</jta-data-source> <class>com.td.waw.cse.entities.Product</class> <properties> <property name="openjpa.Log" value="DefaultLevel=TRACE, Runtime=INFO, Tool=INFO, SQL=TRACE"/> <property name="openjpa.QueryCache" value="net.sf.ehcache.openjpa.datacache.EhCacheQueryCache"/> <property name="openjpa.DataCacheManager" value="net.sf.ehcache.openjpa.datacache.EhCacheDataCacheManager"/> <property name="openjpa.DataCache" value="net.sf.ehcache.openjpa.datacache.EhCacheDataCache"/> <property name="openjpa.RemoteCommitProvider" value="net.sf.ehcache.openjpa.datacache.NoOpRemoteCommitProvider"/> </properties> 

• ehcache.xml

   <ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="ehcache.xsd" updateCheck="true" monitoring="autodetect" dynamicConfig="true" > <defaultCache maxElementsInMemory="1000" eternal="false" timeToIdleSeconds="300" timeToLiveSeconds="600" overflowToDisk="false" memoryStoreEvictionPolicy="LRU" /> <!-- OpenJPA data cache --> <cache name="openjpa" maxElementsInMemory="5000" eternal="false" timeToIdleSeconds="300" timeToLiveSeconds="600" overflowToDisk="false" memoryStoreEvictionPolicy="LRU" /> <!-- OpenJPA query cache --> <cache name="openjpa-querycache" maxElementsInMemory="1000" eternal="false" timeToIdleSeconds="300" timeToLiveSeconds="600" overflowToDisk="false" memoryStoreEvictionPolicy="LRU" /> </ehcache> 

• Product.java

   @Entity @Table(name="PRODUCT") @NamedQueries({@NamedQuery(name="getAllProducts", query = "select products from Product products")}) public class Product implements Serializable {} 

I am not getting any exception but i could not see the ehcache working as nothing specific to ehcache printed in the logs. I would really appreciate if someone can help in this.

Answer 1

Add the following properties in persistence.xml:

<property name="openjpa.QueryCache" value="ehcache"/>
<property name="openjpa.DataCacheManager" value="ehcache"/>

Add the following jars in classpath: ehcache-core-2.4.4.jar , ehcache-openjpa-0.2.0.jar and slf4j-api-1.6.1.jar .

That's all.

Jar Downloads:

• link - http://ehcache.org/downloads/catalog?activated=true
• ehcache-core-2.4.4.jar and slf4j-api-1.6.1.jar - ehcache-core-2.4.4-distribution.tar.gz module
• ehcache-openjpa-0.2.0.jar - ehcache-openjpa-0.2.0-distribution.tar.gz

References

• L2 caching explained - http://blogs.oracle.com/carolmcdonald/entry/jpa_caching
• OpenJPA L2 caching implementation - http://openjpa.apache.org/builds/1.0.2/apache-openjpa-1.0.2/docs/manual/ref_guide_caching.html
• Ehcache OpenJPA implementation - http://www.ehcache.org/documentation/user-guide/openjpa-provider

Answer 2

DataNucleus works perfectly fine with EHCache, with the config specified here http://www.datanucleus.org/products/accessplatform_2_2/jpa/cache.html#ehcache It will print log messages about the L2 cache whenever it is accessed. You don't mention your JPA provider.