【发布时间】：2010-12-21 17:47:25
【问题描述】：
以下简单方法在我的本地计算机上运行良好，但在我将其部署到 App Engine 时会引发 NullPointerException。调用 memberVO 上的任何方法，例如 getId() 都会引发 NullPointerException。我不明白为什么这在我的本地网络上有效，但在 apppot.com 上无效。
出于测试目的，我尝试用原语和字符串替换可序列化对象，但没有一个可以传递给 GAE。全部变为空。
如果有人有任何想法，我还包括日志中的异常。
提前感谢您的任何见解。
奥维尔
@Override
public Boolean updateMember(MemberVO memberVO) {
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
Member member = pm.getObjectById(Member.class, memberVO.getId());
member.setFirstName(memberVO.getFirstName());
member.setLastName(memberVO.getLastName());
pm.makePersistent(member);
} catch (NullPointerException npe) {
npe.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
pm.close();
}
return true;
}
@Override
public Boolean updateMember(MemberVO memberVO) {
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
Member member = pm.getObjectById(Member.class, memberVO.getId());
member.setFirstName(memberVO.getFirstName());
member.setLastName(memberVO.getLastName());
pm.makePersistent(member);
} catch (NullPointerException npe) {
npe.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
pm.close();
}
return true;
}
堆栈跟踪：
12-20 05:23PM 48.523 /rest/member 500 3162ms 3858cpu_ms 8api_cpu_ms 0kb Restlet-Framework/2.0snapshot,gzip(gfe)
72.27.92.51 - - [20/Dec/2010:17:23:51 -0800] "POST /rest/member HTTP/1.1" 500 549 - "Restlet-Framework/2.0snapshot,gzip(gfe)"
"myapp.appspot.com" ms=3162 cpu_ms=3858 api_cpu_ms=8 cpm_usd=0.307323
loading_request=1 pending_ms=977
I 12-20 05:23PM 50.343
javax.servlet.ServletContext log: adapter: [Restlet] Attaching
application: com.myapp.MyApplication@1a3b359 to URI:
W 12-20 05:23PM 51.656
org.restlet.resource.UniformResource doCatch: Exception or error
caught in resource
java.lang.NullPointerException
at com.myapp.MemberResource.updateMember(MemberResource.java:67)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:
57)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImp l.java:
43)
at java.lang.reflect.Method.invoke(Method.java:43)
at org.restlet.resource.ServerResource.doHandle(ServerResource.java:
453)
at org.restlet.resource.ServerResource.post(ServerResource.java:1095)
at org.restlet.resource.ServerResource.doHandle(ServerResource.java:
506)
at
org.restlet.resource.ServerResource.doNegotiatedHandle(ServerResource.java:
563)
at
org.restlet.resource.ServerResource.doConditionalHandle(ServerResource.java :
299)
at org.restlet.resource.ServerResource.handle(ServerResource.java:
821)
at org.restlet.resource.Finder.handle(Finder.java:513)
at org.restlet.routing.Filter.doHandle(Filter.java:156)
at org.restlet.routing.Filter.handle(Filter.java:203)
at org.restlet.routing.Router.doHandle(Router.java:495)
at org.restlet.routing.Router.handle(Router.java:735)
at org.restlet.routing.Filter.doHandle(Filter.java:156)
at org.restlet.routing.Filter.handle(Filter.java:203)
at org.restlet.routing.Filter.doHandle(Filter.java:156)
at org.restlet.routing.Filter.handle(Filter.java:203)
at org.restlet.routing.Filter.doHandle(Filter.java:156)
at
org.restlet.engine.application.StatusFilter.doHandle(StatusFilter.java:
154)
at org.restlet.routing.Filter.handle(Filter.java:203)
at org.restlet.routing.Filter.doHandle(Filter.java:156)
at org.restlet.routing.Filter.handle(Filter.java:203)
at org.restlet.engine.ChainHelper.handle(ChainHelper.java:111)
at
org.restlet.engine.application.ApplicationHelper.handle(ApplicationHelper.j ava:
72)
at org.restlet.Application.handle(Application.java:382)
at org.restlet.routing.Filter.doHandle(Filter.java:156)
at org.restlet.routing.Filter.handle(Filter.java:203)
at org.restlet.routing.Router.doHandle(Router.java:495)
at org.restlet.routing.Router.handle(Router.java:735)
at org.restlet.routing.Filter.doHandle(Filter.java:156)
at org.restlet.routing.Filter.handle(Filter.java:203)
at org.restlet.routing.Router.doHandle(Router.java:495)
at org.restlet.routing.Router.handle(Router.java:735)
at org.restlet.routing.Filter.doHandle(Filter.java:156)
at org.restlet.routing.Filter.handle(Filter.java:203)
at org.restlet.engine.ChainHelper.handle(ChainHelper.java:111)
at org.restlet.Component.handle(Component.java:387)
at org.restlet.Server.handle(Server.java:488)
at org.restlet.engine.ServerHelper.handle(ServerHelper.java:71)
at
org.restlet.engine.http.HttpServerHelper.handle(HttpServerHelper.java:
150)
at org.restlet.ext.servlet.ServerServlet.service(ServerServlet.java:
1037)
at
org.restlet.ext.gwt.GwtShellServletWrapper.service(GwtShellServletWrapper.j ava:
189)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:
511)
at org.mortbay.jetty.servlet.ServletHandler
$CachedChain.doFilter(ServletHandler.java:1166)
at org.mortbay.jetty.servlet.ServletHandler
$CachedChain.doFilter(ServletHandler.java:1157)
at org.mortbay.jetty.servlet.ServletHandler
$CachedChain.doFilter(ServletHandler.java:1157)
at org.mortbay.jetty.servlet.ServletHandler
$CachedChain.doFilter(ServletHandler.java:1157)
at
org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:
388)
at
org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:
216)
at
org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:
182)
at
org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:
765)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:
418)
at
org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:
152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:
542)
at org.mortbay.jetty.HttpConnection
$RequestHandler.headerComplete(HttpConnection.java:923)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at
com.google.net.rpc.impl.BlockingApplicationHandler.handleRequest(BlockingAp plicationHandler.java:
24)
at com.google.net.rpc.impl.RpcUtil.runRpcInApplication(RpcUtil.java:
435)
at com.google.net.rpc.impl.Server$RpcTask.runInContext(Server.java:
572)
at com.google.tracing.TraceContext$TraceContextRunnable
$1.run(TraceContext.java:448)
at com.google.tracing.TraceContext.runInContext(TraceContext.java:
688)
at com.google.tracing.TraceContext
$AbstractTraceContextCallback.runInInheritedContextNoUnref(TraceContext.jav a:
326)
at com.google.tracing.TraceContext
$AbstractTraceContextCallback.runInInheritedContext(TraceContext.java:
318)
at com.google.tracing.TraceContext
$TraceContextRunnable.run(TraceContext.java:446)
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:
1110)
at java.util.concurrent.ThreadPoolExecutor
$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:636)
I 12-20 05:23PM 51.684
This request caused a new process to be started for your application,
and thus caused your application code to be loaded for the first time.
This request may thus take longer and use more CPU than a typical
request for your application.
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