hi:<br><br>in my webapp, I use JPA to store the runtime state,i use this code in VdcService.java which is a sample java class:<br><br><div style="margin-left: 40px;">EntityManagerFactory emf =Persistence.createEntityManagerFactory( "org.drools.persistence.jpa" );<br>
Environment env = KnowledgeBaseFactory.newEnvironment();<br>
env.set( EnvironmentName.ENTITY_MANAGER_FACTORY, emf );<br><br> // create a new knowledge session that uses JPA to store the runtime state<br>StatefulKnowledgeSession ksession = JPAKnowledgeService.newStatefulKnowledgeSession( kbase, null, env );<br>
</div><br>I put persistence.xml to webRoot/META-INF/ , persistence.xml:<br><br><div style="margin-left: 40px;"><?xml version="1.0" encoding="UTF-8" standalone="yes"?><br><persistence<br>
version="1.0"<br> xsi:schemaLocation=<br> "<a href="http://java.sun.com/xml/ns/persistence">http://java.sun.com/xml/ns/persistence</a><br> <a href="http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd</a><br>
<a href="http://java.sun.com/xml/ns/persistence/orm">http://java.sun.com/xml/ns/persistence/orm</a> <br> <a href="http://java.sun.com/xml/ns/persistence/orm_1_0.xsd">http://java.sun.com/xml/ns/persistence/orm_1_0.xsd</a>"<br>
xmlns:orm="<a href="http://java.sun.com/xml/ns/persistence/orm">http://java.sun.com/xml/ns/persistence/orm</a>"<br> xmlns:xsi="<a href="http://www.w3.org/2001/XMLSchema-instance">http://www.w3.org/2001/XMLSchema-instance</a>"<br>
xmlns="<a href="http://java.sun.com/xml/ns/persistence">http://java.sun.com/xml/ns/persistence</a>"><br><br> <persistence-unit name="org.drools.persistence.jpa" transaction-type="JTA"><br>
<provider>org.hibernate.ejb.HibernatePersistence</provider><br> <jta-data-source>java:comp/env/jdbc/mysql</jta-data-source> <br> <class>org.drools.persistence.session.SessionInfo</class><br>
<class>org.drools.persistence.processinstance.ProcessInstanceInfo</class><br> <class>org.drools.persistence.processinstance.ProcessInstanceEventInfo</class><br> <class>org.drools.persistence.processinstance.WorkItemInfo</class><br>
<br><br> <properties><br> <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/> <br> <property name="hibernate.max_fetch_depth" value="3"/><br>
<property name="hibernate.hbm2ddl.auto" value="create" /><br> <property name="hibernate.show_sql" value="true" /> <br> <property name="hibernate.transaction.manager_lookup_class" value="org.hibernate.transaction.BTMTransactionManagerLookup" /><br>
</properties> <br> </persistence-unit><br> <br></persistence><br></div><br>I use resin 3.1.10, $resin-home/conf/resin.conf:<br><br><div style="margin-left: 40px;"> <database><br>
<jndi-name>jdbc/mysql</jndi-name><br> <driver type="org.gjt.mm.mysql.Driver"><br> <url>jdbc:mysql://<a href="http://127.0.0.1:3306/test">127.0.0.1:3306/test</a></url><br>
<user>root</user><br> <password></password><br> </driver><br> <prepared-statement-cache-size>8</prepared-statement-cache-size><br> <max-connections>20</max-connections><br>
<max-idle-time>30s</max-idle-time><br> </database><br></div><br>when i run this webapp , i got this exception:<br>
<br>
java.lang.NullPointerException<br>
at com.caucho.amber.manager.AmberPersistenceProvider.createEntityManagerFactory(AmberPersistenceProvider.java:65)<br>
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:69)<br>
at com.abc.abc.service.VdcService.exec(VdcService.java:32)<br>
at com.abc.abc.resources.Apply.apply(Apply.java:55)<br>
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)<br>
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)<br>
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)<br>
at java.lang.reflect.Method.invoke(Method.java:597)<br>
at
com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:156)<br>
at
com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:67)<br>
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:208)<br>
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:75)<br>
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:115)<br>
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:67)<br>
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:724)<br>
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:689)<br>
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:680)<br>
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:324)<br>
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:425)<br>
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:604)<br>
at javax.servlet.http.HttpServlet.service(HttpServlet.java:91)<br>
at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:103)<br>
at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:416)<br>
at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:87)<br>
at org.apache.struts2.dispatcher.ActionContextCleanUp.doFilter(ActionContextCleanUp.java:99)<br>
at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:87)<br>
at com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:187)<br>
at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:265)<br>
at com.caucho.server.http.HttpRequest.handleRequest(HttpRequest.java:273)<br>
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:682)<br>
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)<br>
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)<br>
at java.lang.Thread.run(Thread.java:619)<br>
<br>i can't solve it.How to solve it?help me ,THS<br>