3:37 a.m.
hi:
in my webapp, I use JPA to store the runtime state,i use this code in
VdcService.java which is a sample java class:
EntityManagerFactory emf =Persistence.createEntityManagerFactory(
"org.drools.persistence.jpa" );
Environment env = KnowledgeBaseFactory.newEnvironment();
env.set( EnvironmentName.ENTITY_MANAGER_FACTORY, emf );
// create a new knowledge session that uses JPA to store the runtime state
StatefulKnowledgeSession ksession =
JPAKnowledgeService.newStatefulKnowledgeSession( kbase, null, env );
I put persistence.xml to webRoot/META-INF/ , persistence.xml:
<?xml version="1.0" encoding="UTF-8"
standalone="yes"?>
<persistence
version="1.0"
xsi:schemaLocation=
"http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd
http://java.sun.com/xml/ns/persistence/orm
http://java.sun.com/xml/ns/persistence/orm_1_0.xsd"
xmlns:orm="http://java.sun.com/xml/ns/persistence/orm"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/persistence">
<persistence-unit name="org.drools.persistence.jpa"
transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jta-data-source>java:comp/env/jdbc/mysql</jta-data-source>
<class>org.drools.persistence.session.SessionInfo</class>
<class>org.drools.persistence.processinstance.ProcessInstanceInfo</class>
<class>org.drools.persistence.processinstance.ProcessInstanceEventInfo</class>
<class>org.drools.persistence.processinstance.WorkItemInfo</class>
<properties>
<property name="hibernate.dialect"
value="org.hibernate.dialect.MySQLDialect"/>
<property name="hibernate.max_fetch_depth"
value="3"/>
<property name="hibernate.hbm2ddl.auto" value="create"
/>
<property name="hibernate.show_sql" value="true" />
<property name="hibernate.transaction.manager_lookup_class"
value="org.hibernate.transaction.BTMTransactionManagerLookup" />
</properties>
</persistence-unit>
</persistence>
I use resin 3.1.10, $resin-home/conf/resin.conf:
<database>
<jndi-name>jdbc/mysql</jndi-name>
<driver type="org.gjt.mm.mysql.Driver">
<url>jdbc:mysql://127.0.0.1:3306/test</url>
<user>root</user>
<password></password>
</driver>
<prepared-statement-cache-size>8</prepared-statement-cache-size>
<max-connections>20</max-connections>
<max-idle-time>30s</max-idle-time>
</database>
when i run this webapp , i got this exception:
java.lang.NullPointerException
at
com.caucho.amber.manager.AmberPersistenceProvider.createEntityManagerFactory(AmberPersistenceProvider.java:65)
at
javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:69)
at com.abc.abc.service.VdcService.exec(VdcService.java:32)
at com.abc.abc.resources.Apply.apply(Apply.java:55)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at
com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:156)
at
com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:67)
at
com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:208)
at
com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:75)
at
com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:115)
at
com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:67)
at
com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:724)
at
com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:689)
at
com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:680)
at
com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:324)
at
com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:425)
at
com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:604)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:91)
at
com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:103)
at
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:416)
at
com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:87)
at
org.apache.struts2.dispatcher.ActionContextCleanUp.doFilter(ActionContextCleanUp.java:99)
at
com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:87)
at
com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:187)
at
com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:265)
at
com.caucho.server.http.HttpRequest.handleRequest(HttpRequest.java:273)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:682)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:619)
i can't solve it.How to solve it?help me ,THS