Hibernate ehCache null pointer exception on put

Here is my config.

<?xml version="1.0" encoding="UTF-8"?>

<ehcache>    
<defaultCache
    maxElementsInMemory="500000"
    eternal="false"
    timeToIdleSeconds="120"
    timeToLiveSeconds="120"
    overflowToDisk="true"
/>
<cache
    name="com.icon.sa.common.dm.PromoItem"
    maxElementsInMemory="500000"
    eternal="false"
    timeToIdleSeconds="300"
    timeToLiveSeconds="600"
    overflowToDisk="true"
/>
<cache
    name="org.hibernate.cache.StandardQueryCache"
    maxElementsInMemory="500000"
    eternal="false"
    timeToLiveSeconds="120"
    overflowToDisk="true"/>
<cache
    name="org.hibernate.cache.UpdateTimestampsCache"
    maxElementsInMemory="500000"
    eternal="true"
    overflowToDisk="true"/>

<cache name="query.PromosBySearchRequestFindAction"
    maxElementsInMemory="500000"
    eternal="false"
    timeToLiveSeconds="86400"
    overflowToDisk="true"/>

</ehcache>

When I try to perform the query.list() I get this exception

Aug 3, 2011 3:10:56 PM org.hibernate.cache.UpdateTimestampsCache <init>
INFO: starting update timestamps cache at region: org.hibernate.cache.UpdateTimestampsCache
Aug 3, 2011 3:10:56 PM org.hibernate.cache.StandardQueryCache <init>
INFO: starting query cache at region: org.hibernate.cache.StandardQueryCache
Time before db: Wed Aug 03 15:10:57 PDT 2011
Aug 3, 2011 3:10:57 PM org.hibernate.cache.StandardQueryCache <init>
INFO: starting query cache at region: query.PromosBySearchRequestFindAction
Aug 3, 2011 3:10:57 PM com.icon.sa.service.action.BaseAction perform
SEVERE: class com.icon.sa.service.action.euser.PromosBySearchRequestFindAction
java.lang.NullPointerException
    at org.hibernate.type.TypeHelper.disassemble(TypeHelper.java:146)
    at org.hibernate.cache.StandardQueryCache.put(StandardQueryCache.java:106)
    at org.hibernate.loader.Loader.putResultInQueryCache(Loader.java:2434)
    at org.hibernate.loader.Loader.listUsingQueryCache(Loader.java:2321)
    at org.hibernate.loader.Loader.list(Loader.java:2268)
    at org.hibernate.loader.custom.CustomLoader.list(CustomLoader.java:316)
    at org.hibernate.impl.SessionImpl.listCustomQuery(SessionImpl.java:1842)
    at org.hibernate.impl.AbstractSessionImpl.list(AbstractSessionImpl.java:165)
    at org.hibernate.impl.SQLQueryImpl.list(SQLQueryImpl.java:157)
    at com.icon.sa.common.dm.dao.PromoItemDao.findAllReleasedBySearchRequest(PromoItemDao.java:121)
    at com.icon.sa.service.action.euser.PromosBySearchRequestFindAction.doWork(PromosBySearchRequestFindAction.java:63)
    at com.icon.sa.service.action.BaseAction.perform(BaseAction.java:61)
    at com.icon.sa.ws.euser.PromosResource.get(PromosResource.java:86)
    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(AbstractResource开发者_如何转开发MethodDispatchProvider.java:168)
    at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:70)
    at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:279)
    at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
    at com.sun.jersey.server.impl.uri.rules.SubLocatorRule.accept(SubLocatorRule.java:121)
    at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
    at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:86)
    at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
    at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:74)
    at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1357)
    at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1289)
    at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1239)
    at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1229)
    at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:420)
    at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:497)
    at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:684)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    at java.lang.Thread.run(Thread.java:662)

---

This has little to do with ehCache per se.

Error is thrown because one (or all) of result types is null.

Judging from the stack trace, you've configured custom loader for your entity. Chances are that either it's not declared correctly (specifically, result class / return alias) or it needs to auto-discover types (is declared as "select * ...") which is not supported in conjunction with caching.