NullPointerException in persist() method

Hi,
I'm new using JPA (TopLinks) and have the following problem:
In a managed bean that uses resource injection, i.e
+@PersistentContext+
private EntityManager em;
when calling em.persist(object) always get a java.lang.NullPointerException, no matter what entity trying to persist.
Somebody can help ?
Thanks in advance
edu

Here is the server log :
06/11/2007 11:59:53 com.sun.enterprise.admin.servermgmt.launch.ASLauncher buildCommand
INFO:
D:/Program Files/Java/jdk1.6.0_02\bin\java
-Dcom.sun.aas.instanceRoot=D:/Program Files/glassfish-v2-b58g/domains/domain1
-Dcom.sun.aas.ClassPathPrefix=
-Dcom.sun.aas.ClassPathSuffix=
-Dcom.sun.aas.ServerClassPath=
-Dcom.sun.aas.classloader.appserverChainJars.ee=
-Dcom.sun.aas.classloader.appserverChainJars=admin-cli.jar,admin-cli-ee.jar,j2ee-svc.jar
-Dcom.sun.aas.classloader.excludesList=admin-cli.jar,appserv-upgrade.jar,sun-appserv-ant.jar
-Dcom.sun.aas.classloader.optionalOverrideableChain.ee=
-Dcom.sun.aas.classloader.optionalOverrideableChain=webservices-rt.jar,webservices-tools.jar
-Dcom.sun.aas.classloader.serverClassPath.ee=/lib/hadbjdbc4.jar,D:/Program Files/glassfish-v2-b58g/lib/SUNWjdmk/5.1/lib/jdmkrt.jar,/lib/dbstate.jar,/lib/hadbm.jar,/lib/hadbmgt.jar,D:/Program Files/glassfish-v2-b58g/lib/SUNWmfwk/lib/mfwk_instrum_tk.jar
-Dcom.sun.aas.classloader.serverClassPath=D:/Program Files/glassfish-v2-b58g/lib/install/applications/jmsra/imqjmsra.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/jaxm-api.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/fscontext.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/imqbroker.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/imqjmx.jar,D:/Program Files/glassfish-v2-b58g/lib/ant/lib/ant.jar,D:/Program Files/glassfish-v2-b58g/lib/SUNWjdmk/5.1/lib/jdmkrt.jar
-Dcom.sun.aas.classloader.sharedChainJars.ee=appserv-se.jar,appserv-ee.jar,jesmf-plugin.jar,/lib/dbstate.jar,/lib/hadbjdbc4.jar,jgroups-all.jar,D:/Program Files/glassfish-v2-b58g/lib/SUNWmfwk/lib/mfwk_instrum_tk.jar
-Dcom.sun.aas.classloader.sharedChainJars=javaee.jar,D:/Program Files/Java/jdk1.6.0_02/lib/tools.jar,install/applications/jmsra/imqjmsra.jar,com-sun-commons-launcher.jar,com-sun-commons-logging.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/jaxm-api.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/fscontext.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/imqbroker.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/imqjmx.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/imqxm.jar,webservices-rt.jar,webservices-tools.jar,mail.jar,appserv-jstl.jar,jmxremote_optional.jar,D:/Program Files/glassfish-v2-b58g/lib/SUNWjdmk/5.1/lib/jdmkrt.jar,activation.jar,appserv-rt.jar,appserv-admin.jar,appserv-cmp.jar,D:/Program Files/glassfish-v2-b58g/updatecenter/lib/updatecenter.jar,D:/Program Files/glassfish-v2-b58g/jbi/lib/jbi.jar,D:/Program Files/glassfish-v2-b58g/imq/lib/imqjmx.jar,D:/Program Files/glassfish-v2-b58g/lib/ant/lib/ant.jar,dbschema.jar
-Dcom.sun.aas.configName=server-config
-Dcom.sun.aas.configRoot=D:/Program Files/glassfish-v2-b58g/config
-Dcom.sun.aas.defaultLogFile=D:/Program Files/glassfish-v2-b58g/domains/domain1/logs/server.log
-Dcom.sun.aas.domainName=domain1
-Dcom.sun.aas.installRoot=D:/Program Files/glassfish-v2-b58g
-Dcom.sun.aas.instanceName=server
-Dcom.sun.aas.processLauncher=SE
-Dcom.sun.aas.promptForIdentity=true
-Dcom.sun.enterprise.config.config_environment_factory_class=com.sun.enterprise.config.serverbeans.AppserverConfigEnvironmentFactory
-Dcom.sun.enterprise.overrideablejavaxpackages=javax.help,javax.portlet
-Dcom.sun.enterprise.taglibs=appserv-jstl.jar,jsf-impl.jar
-Dcom.sun.enterprise.taglisteners=jsf-impl.jar
-Dcom.sun.updatecenter.home=D:/Program Files/glassfish-v2-b58g/updatecenter
-Ddomain.name=domain1
-Djava.endorsed.dirs=D:/Program Files/glassfish-v2-b58g/lib/endorsed
-Djava.ext.dirs=D:/Program Files/Java/jdk1.6.0_02/lib/ext;D:/Program Files/Java/jdk1.6.0_02/jre/lib/ext;D:/Program Files/glassfish-v2-b58g/domains/domain1/lib/ext;D:/Program Files/glassfish-v2-b58g/javadb/lib
-Djava.library.path=D:\Program Files\glassfish-v2-b58g\lib;D:\Program Files\glassfish-v2-b58g\lib;D:\Program Files\glassfish-v2-b58g\bin;D:\Program Files\glassfish-v2-b58g\lib
-Djava.security.auth.login.config=D:/Program Files/glassfish-v2-b58g/domains/domain1/config/login.conf
-Djava.security.policy=D:/Program Files/glassfish-v2-b58g/domains/domain1/config/server.policy
-Djava.util.logging.manager=com.sun.enterprise.server.logging.ServerLogManager
-Djavax.management.builder.initial=com.sun.enterprise.admin.server.core.jmx.AppServerMBeanServerBuilder
-Djavax.net.ssl.keyStore=D:/Program Files/glassfish-v2-b58g/domains/domain1/config/keystore.jks
-Djavax.net.ssl.trustStore=D:/Program Files/glassfish-v2-b58g/domains/domain1/config/cacerts.jks
-Djdbc.drivers=org.apache.derby.jdbc.ClientDriver
-Djmx.invoke.getters=true
-Dsun.rmi.dgc.client.gcInterval=3600000
-Dsun.rmi.dgc.server.gcInterval=3600000
-client
-XX:+UnlockDiagnosticVMOptions
-XX:MaxPermSize=192m
-Xmx512m
-XX:NewRatio=2
-XX:+LogVMOutput
-XX:LogFile=D:/Program Files/glassfish-v2-b58g/domains/domain1/logs/jvm.log
-cp
D:/Program Files/glassfish-v2-b58g/lib/jhall.jar;D:\Program Files\glassfish-v2-b58g\lib\appserv-launch.jar
com.sun.enterprise.server.PELaunch
start
Starting Sun Java System Application Server 9.1 (build b58g-fcs) ...
MBeanServer started: com.sun.enterprise.interceptor.DynamicInterceptor
CORE5098: AS Socket Service Initialization has been completed.
CORE5076: Using [Java HotSpot(TM) Client VM, Version 1.6.0_02] from [Sun Microsystems Inc.]
SEC1002: Security Manager is OFF.
D:/Program Files/glassfish-v2-b58g/domains/domain1/config/.__com_sun_appserv_pid
ADM0001:SunoneInterceptor is now enabled
SEC1143: Loading policy provider com.sun.enterprise.security.provider.PolicyWrapper.
WEB0114: SSO is disabled in virtual server [server]
WEB0114: SSO is disabled in virtual server [__asadmin]
ADM1079: Initialization of AMX MBeans started
ADM1504: Here is the JMXServiceURL for the Standard JMXConnectorServer: [service:jmx:rmi:///jndi/rmi://t0002038990.telecom.arg.telecom.com.ar:8686/jmxrmi]. This is where the remote administrative clients should connect using the standard JMX connectors
ADM1506: Status of Standard JMX Connector: Active = [true]
WEB0302: Starting Sun-Java-System/Application-Server.
JBIFW0010: JBI framework ready to accept requests.
WEB0712: Starting Sun-Java-System/Application-Server HTTP/1.1 on 8080
WEB0712: Starting Sun-Java-System/Application-Server HTTP/1.1 on 8181
WEB0712: Starting Sun-Java-System/Application-Server HTTP/1.1 on 4848
naming.bind
Initializing Sun's JavaServer Faces implementation (1.2_04-b20-p03) for context '/BizChallenge'
SMGT0007: Self Management Rules service is enabled
Application server startup complete.
deployed with moduleid = BizChallenge
naming.bind
Initializing Sun's JavaServer Faces implementation (1.2_04-b20-p03) for context '/BizChallenge'
java.lang.NullPointerException
javax.faces.el.EvaluationException: java.lang.NullPointerException
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:91)
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:91)
at com.sun.rave.web.ui.appbase.faces.ActionListenerImpl.processAction(ActionListenerImpl.java:91)
at javax.faces.component.UICommand.broadcast(UICommand.java:383)
at com.sun.webui.jsf.component.WebuiCommand.broadcast(WebuiCommand.java:160)
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:447)
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:752)
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:97)
at com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:251)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:117)
at com.sun.faces.extensions.avatar.lifecycle.PartialTraversalLifecycle.execute(PartialTraversalLifecycle.java:94)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:244)
at org.apache.catalina.core.ApplicationFilterChain.servletService(ApplicationFilterChain.java:411)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:317)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:198)
at com.sun.webui.jsf.util.UploadFilter.doFilter(UploadFilter.java:267)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:198)
at org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:390)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:198)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:288)
at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:271)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:202)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:632)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:577)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:94)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:206)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:632)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:577)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:571)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1080)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:150)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:632)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:577)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:571)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1080)
at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:270)
at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.invokeAdapter(DefaultProcessorTask.java:637)
at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.doProcess(DefaultProcessorTask.java:568)
at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.process(DefaultProcessorTask.java:813)
at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.executeProcessorTask(DefaultReadTask.java:339)
at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.doTask(DefaultReadTask.java:261)
at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.doTask(DefaultReadTask.java:212)
at com.sun.enterprise.web.connector.grizzly.TaskBase.run(TaskBase.java:265)
at com.sun.enterprise.web.connector.grizzly.ssl.SSLWorkerThread.run(SSLWorkerThread.java:106)
Caused by: java.lang.NullPointerException
at bizchallenge.FormAdmin.persist(FormAdmin.java:32)
at bizchallenge.FormAdmin.saveLoanForm(FormAdmin.java:38)
at bizchallenge.BankLoan.btnEnviar_action(BankLoan.java:379)
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.el.parser.AstValue.invoke(AstValue.java:187)
at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:297)
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:77)
... 45 more

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Hello,
I am trying to reproduce the database sample of the Java Roadmap using EJB's. I have gone through all the steps, deploying went well, compiling too. but when running the selectEJB Client program I get the following messages:
"C:\Program Files\Oracle\JDeveloper 3.1\java\bin\javaw.exe" -mx50m -classpath "U:\Documentation\EJB;C:\Program Files\Oracle\JDeveloper 3.1\lib\jdev-rt.zip;C:\Program Files\Oracle\JDeveloper 3.1\jdbc\lib\oracle8.1.6\classes111.zip;C:\Program Files\Oracle\JDeveloper 3.1\lib\connectionmanager.zip;C:\Program Files\Oracle\JDeveloper 3.1\lib\javax_ejb.zip;C:\Program Files\Oracle\JDeveloper 3.1\aurora\lib\aurora_client.jar;C:\Program Files\Oracle\JDeveloper 3.1\aurora\lib\vbjorb.jar;C:\Program Files\Oracle\JDeveloper 3.1\aurora\lib\vbjapp.jar;C:\Program Files\Oracle\JDeveloper 3.1\aurora\lib\vbjtools.jar;C:\Program Files\Oracle\JDeveloper 3.1\aurora\lib\vbj30ssl.jar;C:\Program Files\Oracle\JDeveloper 3.1\aurora\lib\aurora.zip;C:\Program Files\Oracle\JDeveloper 3.1\sqlj\lib\translator.zip;U:\Documentation\EJB\selectEJBRemoteSource.jar;U:\Documentation\EJB\selectEJBRemoteGenerated.jar;C:\Program Files\Oracle\JDeveloper 3.1\java\lib\classes.zip" selectO8iClient.MyEJBClient
Creating an initial context
Looking for the EJB published as 'test/selectEJBRemote'
Creating a new EJB instance
Caught RuntimeException in remote method; nested exception is:
java.lang.NullPointerException:null
Remote Stack Trace:
java.lang.NullPointerException
at selectEJB.selectEJBClass.ejbCreate(selectEJBClass.java:41)
at oracle.aurora.ejb.gen.test_selectEJBRemote.EjbHome_selectEJBHome.create(EjbHome_selectEJBHome:52)
at selectEJB._tie_selectEJBHome.create(_tie_selectEJBHome.java:53)
at selectEJB._selectEJBHomeImplBase._execute(_selectEJBHomeImplBase.java:65)
at selectEJB._selectEJBHomeImplBase._execute(_selectEJBHomeImplBase.java:53)
at com.visigenic.vbroker.orb.SkeletonDelegateImpl.execute(SkeletonDelegateImpl.java:129)
at oracle.aurora.server.GiopProtocolAdapter.doRequest(GiopProtocolAdapter.java:266)
at com.visigenic.vbroker.orb.GiopProtocolAdapter.dispatchMessage(GiopProtocolAdapter.java:462)
at oracle.aurora.server.ThreadSessionDispatcher.run(ThreadSessionDispatcher.java:92)
at oracle.aurora.server.VCIiopConnection.processRequest(VCIiopConnection.java:62)
at oracle.aurora.server.GiopServer._service(GiopServer.java:82)
at oracle.aurora.server.GiopServer.service(GiopServer.java:191)
at oracle.aurora.net.VirtualCircuit.processRequest(VirtualCircuit.java:201)
at oracle.aurora.net.Presentation.handleRequest(Presentation.java:292)
oracle.aurora.ejb.RemoteRuntimeException: Caught RuntimeException in remote method; nested exception is:
java.lang.NullPointerException:null
Remote Stack Trace:
java.lang.NullPointerException
at selectEJB.selectEJBClass.ejbCreate(selectEJBClass.java:41)
at oracle.aurora.ejb.gen.test_selectEJBRemote.EjbHome_selectEJBHome.create(EjbHome_selectEJBHome:52)
at selectEJB._tie_selectEJBHome.create(_tie_selectEJBHome.java:53)
at selectEJB._selectEJBHomeImplBase._execute(_selectEJBHomeImplBase.java:65)
at selectEJB._selectEJBHomeImplBase._execute(_selectEJBHomeImplBase.java:53)
at com.visigenic.vbroker.orb.SkeletonDelegateImpl.execute(SkeletonDelegateImpl.java:129)
at oracle.aurora.server.GiopProtocolAdapter.doRequest(GiopProtocolAdapter.java:266)
at com.visigenic.vbroker.orb.GiopProtocolAdapter.dispatchMessage(GiopProtocolAdapter.java:462)
at oracle.aurora.server.ThreadSessionDispatcher.run(ThreadSessionDispatcher.java:92)
at oracle.aurora.server.VCIiopConnection.processRequest(VCIiopConnection.java:62)
at oracle.aurora.server.GiopServer._service(GiopServer.java:82)
at oracle.aurora.server.GiopServer.service(GiopServer.java:191)
at oracle.aurora.net.VirtualCircuit.processRequest(VirtualCircuit.java:201)
at oracle.aurora.net.Presentation.handleRequest(Presentation.java:292)
at selectEJB._st_selectEJBHome.create(_st_selectEJBHome.java:68)
at selectO8iClient.MyEJBClient.main(MyEJBClient.java:110)
End...java.io.IOException: read error
I have tried debugging the code and there seems to be a problem with creating the remoteInterface:
selectEJBRemote remoteInterface = homeInterface.create();
I just can't figure out what. Can someone help me?
Thanks,
Benny

I have encountered exactly the same problem when creating a BMP Entity Bean. Has someone found a solution yet ?

NullPointerException in indexing method

Hi,
I'm writing a simple indexing engine, and it works great - if I'm not indexing a lot of files.
It saves the file paths in a text file, but when I try to index the whole hard disk the file gets
about 1,5 MB large before the NullPointerException occurres.
Here's the indexing method:
private void recursiveIndexing(File folder, PrintWriter printWriter)
 File[] filesInDirectory = folder.listFiles();
 for (int i = 0; i < filesInDirectory.length; i++) {
 if (filesInDirectory.isDirectory())
 recursiveIndexing(filesInDirectory[i], printWriter);
 else
 printWriter.println(filesInDirectory[i].getPath());
}Thanks in advance.

Oh, sorry, I was in a hurry when I wrote the post.
Actually it's these two lines who are causing the exception:
for (int i = 0; i < filesInDirectory.length; i++)
recursiveIndexing(filesInDirectory, printWriter);I noticed now, when I tried to index the whole hard drive at my
own computer (which is more powerful than the other one), that
the text file became 6,2 MB large before the exception occurred.
Thanks.
Edited by: Souken on 2008-sep-29 20:17

NullPointerException on object methods

Hello everybody! I just started learning Java yesterday, and am looking forward to contributing to the forum!
Here is a code I was working on today- it's the start of a simple game of blackjack.
import java.util.Scanner;
class BlackJack {
 public static void main(String[] args) {
 Deck deck = new Deck();
 System.out.print("Enter your name > ");
 Scanner in = new Scanner(System.in);
 String name = in.nextLine();
 Hand phand = new Hand(name);
 phand.addCards(2,deck);
 Hand dhand = new Hand("Dealer");
 dhand.addCards(2,deck);
 System.out.println("Dealer: "+dhand.readHand(true));
 System.out.println("You: "+phand.readHand());
 System.out.println(phand.sum);
}Then here is the Deck class:
import java.util.Random;
public class Deck {
 private int[] cards;
 public int getCard() {
 Random generator=new Random();
 int randomInt, out;
 do {randomInt=generator.nextInt(52);}
 while (cards[randomInt]==0);
 out=cards[randomInt];
 cards[randomInt]=0;
 return out;
 public void shuffle() {
 int[] newCards={1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,6,6,6,6,7,7,7,7,8,8,8,8,9,9,9,9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10};
 cards=newCards;
 public Deck() {
 int[] cards = {1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,6,6,6,6,7,7,7,7,8,8,8,8,9,9,9,9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10};
}And here is the Hand class:
public class Hand {
 private int[] cards;
 private int sum;
 public String name;
 public void addCards(int numCards, Deck deck) {
 for (int i=0;i<numCards;i++) {
 int newCard=deck.getCard();
 cards[cards.length]=newCard;
 sum+=newCard;
 public int getSum() {
 return sum;
 public String readHand(boolean isHidden) {
 String out="";
 if (isHidden) {
 out=cards[0]+" x";
 else {
 for (int i=0;i<cards.length;i++) {
 out+=cards[i]+" ";
 return out;
 public String readHand() {
 return readHand(false);
 public Hand(String newName) {
 cards=new int[10];
 sum=0;
 name=newName;
}Now I'm getting this runtime error:
Exception in thread "main" java.lang.NullPointerException
 at Deck.getCard(Deck.java:8)
 at Hand.addCards(Hand.java:7)
 at BlackJack.main(BlackJack.java:9)I found online that the NullPointerException means that the object I'm calling is null, but I can't figure out why. I assume it's a simple thing that I overlooked (or haven't learned yet), but the curious thing is when I commented out the lines which caused the exception, and made the sum from the hand class public, I could use it fine. Any help is greatly appreciated!
-seveneightn9ne

Now compiling Deck results in these errors:
Deck.java:7: cannot find symbol
symbol : variable cards
location: class Deck
 cards = new int[] {1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,6,6,6,6,7,7,7,7,8,8,8,8,9,9,9,9,10,10,10,
10,10,10,10,10,10,10,10,10,10,10,10,10};
 ^
Deck.java:13: cannot find symbol
symbol : variable cards
location: class Deck
 while (cards[randomInt]==0);
 ^
Deck.java:14: cannot find symbol
symbol : variable cards
location: class Deck
 out=cards[randomInt];
 ^
Deck.java:15: cannot find symbol
symbol : variable cards
location: class Deck
 cards[randomInt]=0;
 ^
Deck.java:20: cannot find symbol
symbol : variable cards
location: class Deck
 cards=newCards;
 ^
5 errorsHere is what Deck currently looks like:
import java.util.Random;
public class Deck {
 public Deck() {
 cards = new int[] {1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,6,6,6,6,7,7,7,7,8,8,8,8,9,9,9,9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10};
 public int getCard() {
 Random generator=new Random();
 int randomInt, out;
 do {randomInt=generator.nextInt(52);}
 while (cards[randomInt]==0);
 out=cards[randomInt];
 cards[randomInt]=0;
 return out;
 public void shuffle() {
 int[] newCards={1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,6,6,6,6,7,7,7,7,8,8,8,8,9,9,9,9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10};
 cards=newCards;
}Is it correct that cards is not declared outside the constructor, or is that the cause of the error?

Method persist() don't persist the data.

Hello Experts
I have a problem whem i persist a entity.
Often the instance of entity don't persist when i call method persist().
I don't know what happen. The method don't cause any error, but don't have any registry in the database after passing the persist() method.
Att.
Marcos

Hi Adrian
Thanks for your quickly reply.
i don't use the method flush. But in other entity, i do the same process and the data is commit in database. i've compared these two entity, and they are equals. the only diference is the quantity of attributes in both.
I try to use the method flush in both entity. In the first is OK, the data is commited. In the second cause one error.
When i don't use the method flush, the same happend, the first commit, the second don't commit, but don't cause error.
Waiting for anwser.
Thanks.
Marcos.

JPA and JSF - Problem persisting object

Hi all.
I'm having some trouble with JPA, persisting an object to a MySQL table.
Let's say I have a simple bean, Message:
package my.package
import java.io.Serializable;
import javax.persistence.Id;
import javax.persistence.Entity;
import javax.persistence.Column;
import javax.persistence.Table;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
@Entity
@Table(name="messages")
public class Message implements Serializable {
 @Id
 @GeneratedValue(strategy=GenerationType.AUTO)
 private int id;
 @Column(name="message_text")
 private String message;
 @Column(name="message_author")
 private String author;
 public String getMessage() {
 return this.message;
 public void setMessage(String message) {
 this.message = message;
 public String getAuthor() {
 return this.author;
 public void setAuthor(String author) {
 this.author = author;
}And a controller for this Message bean:
package my.package;
import javax.annotation.Resource;
import javax.persistence.Query;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.PersistenceUnit;
import javax.transaction.UserTransaction;
public class MessageController {
 @PersistenceUnit(unitName="em1")
 private EntityManagerFactory emf;
 @Resource
 private UserTransaction utx;
 private Message message;
 public Message getMessage() {
 return this.message;
 public void setMessage(Message message) {
 this.message = message;
 public String save() {
 EntityManager em = null;
 String returnValue = "";
 try {
 em = this.emf.createEntityManager();
 utx.begin();
 em.persist(this.message);
 utx.commit();
 returnValue = "success";
 } catch(Exception e) {
 e.printStackTrace();
 returnValue = "failure";
 return returnValue;
}Relevant code from the faces-config.xml:
<managed-bean>
 <managed-bean-name>MessageController</managed-bean-name>
 <managed-bean-class>my.package.MessageController</managed-bean-class>
 <managed-bean-scope>request</managed-bean-scope>
 <managed-property>
 <property-name>message</property-name>
 <property-class>my.package.Message</property-class>
 <value>#{Message}</value>
 </managed-property>
</managed-bean>
<managed-bean>
 <managed-bean-name>Message</managed-bean-name>
 <managed-bean-class>my.package.Message</managed-bean-class>
 <managed-bean-scope>request</managed-bean-scope>
</managed-bean>This is my simple persistence.xml:
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0"
 xmlns="http://java.sun.com/xml/ns/persistence"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
 <persistence-unit name ="em1">
 <jta-data-source>jdbc/__glfish</jta-data-source>
 </persistence-unit>
</persistence>The __glfish resource is all set up via Glassfish to point to my MySQL server, via a MySQLPool.
Can anyone see what I'm doing wrong? The Message doesn't get added to the table in my database, and I get a NullPointerException in the method MessageController.save() on the property MessageController.message - which I have specified in the faces-config.xml. Shouldn't that be enough? What have I missed?

Ok, I have (re-)located the problem. It's not my Message property which gets a NullPointerException - it seems like the problem is with my EntityManagerFactory instance. The PersistenceUnit don't get assigned, even though I declare it in my persistence.xml file.
Maybe it is something wrong with my file structure?
The .war file have this structure:
- WEB-INF
 - classes
 - my
 - package
 Message.class
 MessageController.class
 - lib
 [external jars goes here]
 - META-INF
 persistence.xml
 faces-config.xml
 web.xml
[*.jsp/*.xhtml goes here]Can anyone see what's wrong?

Adf faces command button, bindings and ejb 3.0 persisting problem

When mapping the persist method to an adf command button it got this error:
1. JBO-29000: java.lang.IllegalArgumentException: PERSIST impossible sur l'objet détaché : hr.entity.Departments@1b21.; nested exception is: java.lang.IllegalArgumentException: PERSIST impossible sur l'objet détaché : hr.entity.Departments@1b21. -
2. java.lang.IllegalArgumentException: PERSIST impossible sur l'objet détaché : hr.entity.Departments@1b21.; nested exception is: java.lang.IllegalArgumentException: PERSIST impossible sur l'objet détaché : hr.entity.Departments@1b21. -
Is that because Departments are serialized by the container when the session bean is accessed by the data control to catch the data when the form is populating and entities are detached from the persisting context ? or something else ?
I bind the button to the current row data provider for the departments. Is it correct, isn't ?

When mapping the persist method to an adf command button it got this error:
1. JBO-29000: java.lang.IllegalArgumentException: PERSIST impossible sur l'objet détaché : hr.entity.Departments@1b21.; nested exception is: java.lang.IllegalArgumentException: PERSIST impossible sur l'objet détaché : hr.entity.Departments@1b21. -
2. java.lang.IllegalArgumentException: PERSIST impossible sur l'objet détaché : hr.entity.Departments@1b21.; nested exception is: java.lang.IllegalArgumentException: PERSIST impossible sur l'objet détaché : hr.entity.Departments@1b21. -
Is that because Departments are serialized by the container when the session bean is accessed by the data control to catch the data when the form is populating and entities are detached from the persisting context ? or something else ?
I bind the button to the current row data provider for the departments. Is it correct, isn't ?

Getting the object id after persisting

Is there an easy way of getting the object id after using the persist method? I tried the following code piece but it didn't work. Do I have to run a query? I'm new to JPA and waiting for your suggestions. Thanks..
Bill b = new Bill(); .... .... entityManager.persist(b); int id = b.getId()

I tried flushing and refreshing the entity but got an EntityNotFoundException.
Bill b = new Bill();
entityManager.persist(b);
entityManager.flush();
entityManager.refresh(b); // Here where the exception is thrown
int id = b.getId();When I try without refresh, it still get no id

Cannot invoke method multiply() on null object

Hi ,
when im trying to follow Developing Rich Web Applications With Oracle ADF tutorial in this link http://docs.oracle.com/cd/E18941_01/tutorials/jdtut_11r2_55/jdtut_11r2_55_3.html
and in the part ( Add CRUD Operation Components to your Page ) when pressing the CreateInsert i got the error message Cannot invoke method multiply() on null object ,
the logs as below
<Utils> <buildFacesMessage> ADF: Adding the following JSF error message: Cannot invoke method multiply() on null object
java.lang.NullPointerException: Cannot invoke method multiply() on null object
 at org.codehaus.groovy.runtime.NullObject.invokeMethod(NullObject.java:77)
 at org.codehaus.groovy.runtime.InvokerHelper.invokePogoMethod(InvokerHelper.java:750)
 at org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:727)
 at org.codehaus.groovy.runtime.callsite.NullCallSite.call(NullCallSite.java:17)
 at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:40)
 at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite.call(PojoMetaMethodSite.java:54)
 at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:125)
 at bc4j_model_EmpDetails_AnnualSalary_null_gs.run(bc4j_model_EmpDetails_AnnualSalary_null_gs.groovy:1)
 at oracle.jbo.ExprEval.internalEvaluateGroovyScript(ExprEval.java:1200)
 at oracle.jbo.ExprEval.doEvaluate(ExprEval.java:1253)
 at oracle.jbo.ExprEval.evaluateForRow(ExprEval.java:1075)
 at oracle.jbo.server.AttributeDefImpl.evaluateTransientExpression(AttributeDefImpl.java:2131)
 at oracle.jbo.server.ViewRowStorage.getAttributeInternal(ViewRowStorage.java:1827)
 at oracle.jbo.server.ViewRowImpl.getAttributeValue(ViewRowImpl.java:1962)
 at oracle.jbo.server.ViewRowImpl.getAttributeInternal(ViewRowImpl.java:824)
 at oracle.jbo.server.ViewRowImpl.getAttrInvokeAccessor(ViewRowImpl.java:906)
 at oracle.jbo.server.ViewRowImpl.getAttribute(ViewRowImpl.java:854)
 at oracle.jbo.uicli.binding.JUCtrlValueBinding.internalGetAttributeValueFromRow(JUCtrlValueBinding.java:1213)
 at oracle.jbo.uicli.binding.JUCtrlValueBinding.getAttributeFromRow(JUCtrlValueBinding.java:764)
 at oracle.jbo.uicli.binding.JUCtrlValueBinding.getInputValueInRow(JUCtrlValueBinding.java:3004)
 at oracle.jbo.uicli.binding.JUCtrlValueBinding.getInputValue(JUCtrlValueBinding.java:2852)
 at oracle.jbo.uicli.binding.JUCtrlValueBinding.getInputValue(JUCtrlValueBinding.java:2841)
 at oracle.adfinternal.view.faces.model.binding.FacesCtrlAttrsBinding.getInputValue(FacesCtrlAttrsBinding.java:183)
 at oracle.jbo.uicli.binding.JUCtrlValueBinding.internalGet(JUCtrlValueBinding.java:2416)
 at oracle.adfinternal.view.faces.model.binding.FacesCtrlAttrsBinding.internalGet(FacesCtrlAttrsBinding.java:275)
 at oracle.adf.model.binding.DCControlBinding.get(DCControlBinding.java:749)
 at javax.el.MapELResolver.getValue(MapELResolver.java:164)
 at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
 at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
 at com.sun.el.parser.AstValue.getValue(Unknown Source)
 at com.sun.el.ValueExpressionImpl.getValue(Unknown Source)
 at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
 at org.apache.myfaces.trinidad.bean.FacesBeanImpl.getProperty(FacesBeanImpl.java:73)
 at oracle.adfinternal.view.faces.renderkit.rich.ValueRenderer.getValue(ValueRenderer.java:184)
 at oracle.adfinternal.view.faces.renderkit.rich.SimpleInputBaseRenderer.renderContentStyleAttributes(SimpleInputBaseRenderer.java:512)
 at oracle.adfinternal.view.faces.renderkit.rich.SimpleInputBaseRenderer.renderNonElementContent(SimpleInputBaseRenderer.java:397)
 at oracle.adfinternal.view.faces.renderkit.rich.FormInputRenderer.encodeAllAsNonElement(FormInputRenderer.java:300)
 at oracle.adfinternal.view.faces.renderkit.rich.FormElementRenderer.encodeAll(FormElementRenderer.java:160)
 at oracle.adf.view.rich.render.RichRenderer.delegateRenderer(RichRenderer.java:1700)
 at oracle.adfinternal.view.faces.renderkit.rich.LabeledInputRenderer.renderFieldCellContents(LabeledInputRenderer.java:228)
 at oracle.adfinternal.view.faces.renderkit.rich.LabelLayoutRenderer.renderFieldCell(LabelLayoutRenderer.java:528)
 at oracle.adfinternal.view.faces.renderkit.rich.LabelLayoutRenderer.encodeAll(LabelLayoutRenderer.java:305)
 at oracle.adfinternal.view.faces.renderkit.rich.LabeledInputRenderer.encodeAll(LabeledInputRenderer.java:215)
 at oracle.adf.view.rich.render.RichRenderer.encodeAll(RichRenderer.java:1452)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeEnd(CoreRenderer.java:511)
 at org.apache.myfaces.trinidad.component.UIXComponentBase.encodeEnd(UIXComponentBase.java:923)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1659)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeChild(CoreRenderer.java:624)
 at oracle.adf.view.rich.render.RichRenderer.encodeChild(RichRenderer.java:3201)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelFormLayoutRenderer._encodeFormItem(PanelFormLayoutRenderer.java:1088)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelFormLayoutRenderer.access$100(PanelFormLayoutRenderer.java:50)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelFormLayoutRenderer$FormColumnEncoder.processComponent(PanelFormLayoutRenderer.java:1604)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelFormLayoutRenderer$FormColumnEncoder.processComponent(PanelFormLayoutRenderer.java:1523)
 at org.apache.myfaces.trinidad.component.UIXComponent.processFlattenedChildren(UIXComponent.java:187)
 at org.apache.myfaces.trinidad.component.UIXComponent.processFlattenedChildren(UIXComponent.java:318)
 at org.apache.myfaces.trinidad.component.UIXComponent.encodeFlattenedChildren(UIXComponent.java:283)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelFormLayoutRenderer._encodeChildren(PanelFormLayoutRenderer.java:420)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelFormLayoutRenderer.encodeAll(PanelFormLayoutRenderer.java:208)
 at oracle.adf.view.rich.render.RichRenderer.encodeAll(RichRenderer.java:1452)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeEnd(CoreRenderer.java:511)
 at org.apache.myfaces.trinidad.component.UIXComponentBase.encodeEnd(UIXComponentBase.java:923)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1659)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeChild(CoreRenderer.java:624)
 at oracle.adf.view.rich.render.RichRenderer.encodeChild(RichRenderer.java:3201)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelGroupLayoutRenderer._encodeChild(PanelGroupLayoutRenderer.java:447)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelGroupLayoutRenderer.access$1500(PanelGroupLayoutRenderer.java:30)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelGroupLayoutRenderer$EncoderCallback.processComponent(PanelGroupLayoutRenderer.java:734)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelGroupLayoutRenderer$EncoderCallback.processComponent(PanelGroupLayoutRenderer.java:637)
 at org.apache.myfaces.trinidad.component.UIXComponent.processFlattenedChildren(UIXComponent.java:187)
 at org.apache.myfaces.trinidad.component.UIXComponent.processFlattenedChildren(UIXComponent.java:318)
 at org.apache.myfaces.trinidad.component.UIXComponent.encodeFlattenedChildren(UIXComponent.java:283)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelGroupLayoutRenderer.encodeAll(PanelGroupLayoutRenderer.java:360)
 at oracle.adf.view.rich.render.RichRenderer.encodeAll(RichRenderer.java:1452)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeEnd(CoreRenderer.java:511)
 at org.apache.myfaces.trinidad.component.UIXComponentBase.encodeEnd(UIXComponentBase.java:923)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1659)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeChild(CoreRenderer.java:624)
 at oracle.adf.view.rich.render.RichRenderer.encodeChild(RichRenderer.java:3201)
 at oracle.adfinternal.view.faces.renderkit.rich.DecorativeBoxRenderer.encodeFacet(DecorativeBoxRenderer.java:440)
 at oracle.adfinternal.view.faces.renderkit.rich.DecorativeBoxRenderer._encodeCenterPane(DecorativeBoxRenderer.java:704)
 at oracle.adfinternal.view.faces.renderkit.rich.DecorativeBoxRenderer.encodeAll(DecorativeBoxRenderer.java:380)
 at oracle.adf.view.rich.render.RichRenderer.encodeAll(RichRenderer.java:1452)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeEnd(CoreRenderer.java:511)
 at org.apache.myfaces.trinidad.component.UIXComponentBase.encodeEnd(UIXComponentBase.java:923)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1659)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeChild(CoreRenderer.java:624)
 at oracle.adf.view.rich.render.RichRenderer.encodeChild(RichRenderer.java:3201)
 at oracle.adfinternal.view.faces.renderkit.rich.DecorativeBoxRenderer.encodeFacet(DecorativeBoxRenderer.java:440)
 at oracle.adfinternal.view.faces.renderkit.rich.DecorativeBoxRenderer._encodeCenterPane(DecorativeBoxRenderer.java:704)
 at oracle.adfinternal.view.faces.renderkit.rich.DecorativeBoxRenderer.encodeAll(DecorativeBoxRenderer.java:380)
 at oracle.adf.view.rich.render.RichRenderer.encodeAll(RichRenderer.java:1452)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeEnd(CoreRenderer.java:511)
 at org.apache.myfaces.trinidad.component.UIXComponentBase.encodeEnd(UIXComponentBase.java:923)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1659)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeChild(CoreRenderer.java:624)
 at oracle.adf.view.rich.render.RichRenderer.encodeChild(RichRenderer.java:3201)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelStretchLayoutRenderer.encodeCenterFacet(PanelStretchLayoutRenderer.java:879)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelStretchLayoutRenderer._encodeCenterPane(PanelStretchLayoutRenderer.java:1294)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelStretchLayoutRenderer._encodeMiddlePanes(PanelStretchLayoutRenderer.java:351)
 at oracle.adfinternal.view.faces.renderkit.rich.PanelStretchLayoutRenderer.encodeAll(PanelStretchLayoutRenderer.java:316)
 at oracle.adf.view.rich.render.RichRenderer.encodeAll(RichRenderer.java:1452)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeEnd(CoreRenderer.java:511)
 at org.apache.myfaces.trinidad.component.UIXComponentBase.encodeEnd(UIXComponentBase.java:923)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1659)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeChild(CoreRenderer.java:624)
 at oracle.adf.view.rich.render.RichRenderer.encodeChild(RichRenderer.java:3201)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeAllChildren(CoreRenderer.java:641)
 at oracle.adf.view.rich.render.RichRenderer.encodeAllChildrenInContext(RichRenderer.java:3062)
 at oracle.adfinternal.view.faces.renderkit.rich.FormRenderer.encodeAll(FormRenderer.java:274)
 at oracle.adf.view.rich.render.RichRenderer.encodeAll(RichRenderer.java:1452)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeEnd(CoreRenderer.java:511)
 at org.apache.myfaces.trinidad.component.UIXComponentBase.encodeEnd(UIXComponentBase.java:923)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1659)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeChild(CoreRenderer.java:624)
 at oracle.adf.view.rich.render.RichRenderer.encodeChild(RichRenderer.java:3201)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeAllChildren(CoreRenderer.java:641)
 at oracle.adf.view.rich.render.RichRenderer.encodeAllChildrenInContext(RichRenderer.java:3062)
 at oracle.adfinternal.view.faces.renderkit.rich.DocumentRenderer.encodeAll(DocumentRenderer.java:1277)
 at oracle.adf.view.rich.render.RichRenderer.encodeAll(RichRenderer.java:1452)
 at org.apache.myfaces.trinidad.render.CoreRenderer.encodeEnd(CoreRenderer.java:511)
 at org.apache.myfaces.trinidad.component.UIXComponentBase.encodeEnd(UIXComponentBase.java:923)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1659)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1655)
 at oracle.adfinternal.view.faces.component.AdfViewRoot.encodeAll(AdfViewRoot.java:91)
 at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:399)
 at org.apache.myfaces.trinidadinternal.application.ViewDeclarationLanguageFactoryImpl$ChangeApplyingVDLWrapper.renderView(ViewDeclarationLanguageFactoryImpl.java:350)
 at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131)
 at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:273)
 at org.apache.myfaces.trinidadinternal.application.ViewHandlerImpl.renderView(ViewHandlerImpl.java:165)
 at oracle.adfinternal.view.faces.lifecycle.LifecycleImpl._renderResponse(LifecycleImpl.java:1027)
 at oracle.adfinternal.view.faces.lifecycle.LifecycleImpl._executePhase(LifecycleImpl.java:334)
 at oracle.adfinternal.view.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:232)
 at javax.faces.webapp.FacesServlet.service(FacesServlet.java:313)
 at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:227)
 at weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:125)
 at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:300)
 at weblogic.servlet.internal.TailFilter.doFilter(TailFilter.java:26)
 at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
 at oracle.adf.model.servlet.ADFBindingFilter.doFilter(ADFBindingFilter.java:173)
 at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
 at oracle.adfinternal.view.faces.webapp.rich.RegistrationFilter.doFilter(RegistrationFilter.java:122)
 at org.apache.myfaces.trinidadinternal.webapp.TrinidadFilterImpl$FilterListChain.doFilter(TrinidadFilterImpl.java:468)
 at oracle.adfinternal.view.faces.activedata.AdsFilter.doFilter(AdsFilter.java:60)
 at org.apache.myfaces.trinidadinternal.webapp.TrinidadFilterImpl$FilterListChain.doFilter(TrinidadFilterImpl.java:468)
 at org.apache.myfaces.trinidadinternal.webapp.TrinidadFilterImpl._doFilterImpl(TrinidadFilterImpl.java:293)
 at org.apache.myfaces.trinidadinternal.webapp.TrinidadFilterImpl.doFilter(TrinidadFilterImpl.java:199)
 at org.apache.myfaces.trinidad.webapp.TrinidadFilter.doFilter(TrinidadFilter.java:92)
 at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
 at oracle.adf.library.webapp.LibraryFilter.doFilter(LibraryFilter.java:180)
 at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
 at oracle.security.jps.ee.http.JpsAbsFilter$1.run(JpsAbsFilter.java:111)
 at java.security.AccessController.doPrivileged(Native Method)
 at oracle.security.jps.util.JpsSubject.doAsPrivileged(JpsSubject.java:313)
 at oracle.security.jps.ee.util.JpsPlatformUtil.runJaasMode(JpsPlatformUtil.java:413)
 at oracle.security.jps.ee.http.JpsAbsFilter.runJaasMode(JpsAbsFilter.java:94)
 at oracle.security.jps.ee.http.JpsAbsFilter.doFilter(JpsAbsFilter.java:161)
 at oracle.security.jps.ee.http.JpsFilter.doFilter(JpsFilter.java:71)
 at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
 at oracle.dms.servlet.DMSServletFilter.doFilter(DMSServletFilter.java:136)
 at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
 at weblogic.servlet.internal.RequestEventsFilter.doFilter(RequestEventsFilter.java:27)
 at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
 at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.wrapRun(WebAppServletContext.java:3715)
 at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3681)
 at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
 at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120)
 at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2277)
 at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2183)
 at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1454)
 at weblogic.work.ExecuteThread.execute(ExecuteThread.java:209)
 at weblogic.work.ExecuteThread.run(ExecuteThread.java:178)
<Utils> <buildFacesMessage> ADF: Adding the following JSF error message: Cannot invoke method multiply() on null object
any help please ?

Thanks Frank ,
really i've already downloaded the ZIP of the final application , but the same error message ,
when removing the Annual salary ( Which is a new Attribute ( not DB column) Salary * 12 ) every think is fine and no more error message ,there is no null salary all the employees have a salary , my JDeveloper Version is 11.1.2.1.0
also , because of the EmpDetails is based on the query
FROM EMPLOYEES Employees, DEPARTMENTS Departments
WHERE Employees.DEPARTMENT_ID = Departments.DEPARTMENT_ID
and the Department id is non editable value , that means even if you add a new user u cant never check this user in this interface , u can check this user only on DB (SQL) level .
Edited by: 876602 on Jul 1, 2012 5:17 AM

Input/Output And Method Not Found Problem

Ok so firstly I think I should apologise on two fronts.
Firstly, 'cause this is probably posted in the wrong board but I'm not sure this was suitable for the Swing board just 'cause I've been using Swing? And secondly 'cause the code I'm gonna post is so shoddy I would think this constitutes as flaim-bait. >_>
In my defense this is purely for a little class project to give something to write some documentation on so I'm really not too bothered about the efficiency or ace-mazingness of the end result. I just want it to work.
To the problem at hand.
I'm trying to write a program that asks the user a question and then outputs their answer to a file, from which a tally of answers can later be made for the purpose of displaying "results".
My problem is I've been having problems with the input/output of saving the answers given to the program.
I'm still learning and input/output is probably my weakest subject (other than, y'know, being good at Java). I've had a bash at it in the following code but all it does it overwrite what is in the file with a single answer so no list of results accumulate. I generally don't have an idea what to try for that one so any pointers would be appreciated.
Also, my second problem is, in trying to gather results by tallying what is contained in the file, I've run across a problem with the charAt() method not being found and I'm not sure why. Isn't that method a part of java.lang?
Here's the code thus far:
//libraries
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.text.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
import java.text.*;
import java.io.*;
class CaseStudy {
 public static void main(String args[]) {
 GUI maininterface = new GUI();
 maininterface.setupMenu();
 maininterface.display();
class GUI {
 //for the actionlisteners
 int whatframe = 0;
 //creates mainframe and border content panel
 JFrame mainframe = new JFrame("Survey Client");
 JPanel borderpanel = new JPanel(), bottompanel = new JPanel();
 JButton quizbutton = new JButton("Take the quiz"), tallybutton = new JButton("Show Results"), submitbutton = new JButton("Submit Results"), menubutton = new JButton("Return To Menu");
 QuizQuestions toppanel = new QuizQuestions();
 QuizResults toppanel2 = new QuizResults();
 GUI() {
 //sets border in borderpanel, this spaces the main content in from the sides of the window
 borderpanel.setBorder(BorderFactory.createEmptyBorder(10,10,10,10));
 //sets up the frame and panels and adds on borders
 mainframe.setDefaultCloseOperation(mainframe.EXIT_ON_CLOSE); // exits java when clicking on close on main frame
 mainframe.getContentPane().add(borderpanel); // adds the panel as a component to the frame, the panel can hold stuffs
 borderpanel.setLayout(new BoxLayout(borderpanel, BoxLayout.PAGE_AXIS));// page_axis means it'll layout vertically
 bottompanel.setLayout(new BoxLayout(bottompanel, BoxLayout.LINE_AXIS));// line_axis means it'll layout horizontally
 //gives button an action
 quizbutton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e1) {
 setupQuiz();
 tallybutton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e1) {
 if(whatframe == 1) setupResults();
 else {
 int rusure = JOptionPane.showConfirmDialog(null, "Are you sure you wish to show results? Any current quiz answers won't be saved.", "Please Choose One", JOptionPane.YES_NO_OPTION);
 if(rusure == JOptionPane.YES_OPTION) setupResults();
 menubutton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e1) {
 setupMenu();
 submitbutton.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e1) {
 toppanel.doQuiz();
 borderpanel.add(bottompanel);
 public void setupMenu() {
 if(whatframe == 3) {
 bottompanel.remove(menubutton);
 borderpanel.remove(toppanel2);
 whatframe = 1;
 //adds components and lays them out
 bottompanel.add(quizbutton);
 bottompanel.add(Box.createRigidArea(new Dimension(0,10)));
 bottompanel.add(tallybutton);
 display();
 public void setupQuiz() {
 bottompanel.remove(quizbutton);
 bottompanel.remove(Box.createRigidArea(new Dimension(0,10)));
 bottompanel.remove(tallybutton);
 whatframe = 2;
 bottompanel.add(submitbutton);
 bottompanel.add(Box.createRigidArea(new Dimension(0,10)));
 bottompanel.add(tallybutton);
 borderpanel.add(toppanel);
 display();
 public void setupResults() {
 if(whatframe == 1) {
 bottompanel.remove(quizbutton);
 bottompanel.remove(Box.createRigidArea(new Dimension(0,10)));
 bottompanel.remove(tallybutton);
 else {
 bottompanel.remove(submitbutton);
 bottompanel.remove(Box.createRigidArea(new Dimension(0,10)));
 bottompanel.remove(tallybutton);
 borderpanel.remove(toppanel);
 whatframe = 3;
 bottompanel.add(menubutton);
 borderpanel.add(toppanel2);
 display();
 public void display() {
 //sets the size of the frame around it's components and then shows it
 mainframe.pack();
 mainframe.setVisible(true);
 mainframe.validate(); //makes referenced container relayout it's components
class QuizQuestions extends JPanel {
 LoadingSaving loadsave = new LoadingSaving();
 JPanel popm = new JPanel(), pop1 = new JPanel(), pop2 = new JPanel(), pop3 = new JPanel(), pop4 = new JPanel();
 JFormattedTextField ques = new JFormattedTextField(), op1 = new JFormattedTextField(), op2 = new JFormattedTextField(), op3 = new JFormattedTextField(), op4 = new JFormattedTextField();
 JButton bop1 = new JButton("1"), bop2 = new JButton("2"), bop3 = new JButton("3"), bop4 = new JButton("4");
 char answer;
 QuizQuestions() {
 popm.setLayout(new BoxLayout(popm, BoxLayout.PAGE_AXIS));
 pop1.setLayout(new BoxLayout(pop1, BoxLayout.LINE_AXIS));
 pop2.setLayout(new BoxLayout(pop2, BoxLayout.LINE_AXIS));
 pop3.setLayout(new BoxLayout(pop3, BoxLayout.LINE_AXIS));
 pop4.setLayout(new BoxLayout(pop4, BoxLayout.LINE_AXIS));
 this.add(popm);
 popm.add(ques);
 popm.add(pop1);
 popm.add(pop2);
 popm.add(pop3);
 popm.add(pop4);
 pop1.add(op1);
 pop1.add(bop1);
 pop2.add(op2);
 pop2.add(bop2);
 pop3.add(op3);
 pop3.add(bop3);
 pop4.add(op4);
 pop4.add(bop4);
 //sets up question text fields
 ques.setEditable(false);
 op1.setEditable(false);
 op2.setEditable(false);
 op3.setEditable(false);
 op4.setEditable(false);
 bop1.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e1) {
 answer = 'a';
 bop2.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e1) {
 answer = 'b';
 bop3.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e1) {
 answer = 'c';
 bop4.addActionListener(new ActionListener() {
 public void actionPerformed(ActionEvent e1) {
 answer = 'd';
 Question1();
 public void doQuiz() {
 loadsave.save(answer);
 public void Question1() {
 ques.setValue("Who's your favourite X-Men character?");
 op1.setValue("Cyclops");
 op2.setValue("Xavier");
 op3.setValue("Wolverine");
 op4.setValue("Rogue");
class QuizResults extends JPanel {
 LoadingSaving loadsave = new LoadingSaving();
 JPanel popm = new JPanel();
 JFormattedTextField op1 = new JFormattedTextField(), op2 = new JFormattedTextField(), op3 = new JFormattedTextField(), op4 = new JFormattedTextField();
 int[] answerarray = new int[4];
 QuizResults() {
 popm.setLayout(new BoxLayout(popm, BoxLayout.PAGE_AXIS));
 this.add(popm);
 popm.add(op1);
 popm.add(op2);
 popm.add(op3);
 popm.add(op4);
 op1.setEditable(false);
 op2.setEditable(false);
 op3.setEditable(false);
 op4.setEditable(false);
 answerarray = loadsave.load();
 op1.setValue(answerarray[0]);
 op2.setValue(answerarray[1]);
 op3.setValue(answerarray[2]);
 op4.setValue(answerarray[3]);
class LoadingSaving {
 public void save(char answer) {
 FileReader fr;
 FileWriter fw;
 BufferedReader br;
 String s;
 try {
 //ERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERROR
 fr = new FileReader("casestudyoutput.txt");
 fw = new FileWriter("casestudyoutput.txt");
 br = new BufferedReader(fr);
 if (br.readLine() == null) s = "x";
 else s = br.readLine();
 s = s + answer;
 fw.write(s);
 fr.close();
 fw.close();
 //ERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERROR
 catch(FileNotFoundException exc) {
 JOptionPane.showMessageDialog(null, "File not found.");
 return;
 catch(IOException exc) {
 JOptionPane.showMessageDialog(null, "Something bad happened.");
 return;
 public int[] load() {
 FileReader fr;
 BufferedReader br;
 int[] answerarray = new int[3];
 String s;
 long length;
 int a = 0, b = 0, c = 0, d = 0;
 answerarray[0] = 0;
 answerarray[1] = 0;
 answerarray[2] = 0;
 answerarray[3] = 0;
 try {
 fr = new FileReader("casestudyoutput.txt");
 br = new BufferedReader(fr);
 if (br.readLine() == null) return answerarray;
 else s = br.readLine();
 length = s.length();
 for(int i = 0; i < length; i++) {
 char ch = charAt(i); //ERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERRORERROR
 switch(ch) {
 case 'a':
 a++;
 break;
 case 'b':
 b++;
 break;
 case 'c':
 c++;
 break;
 case 'd':
 d++;
 break;
 answerarray[0] = a;
 answerarray[1] = b;
 answerarray[2] = c;
 answerarray[3] = d;
 fr.close();
 catch(FileNotFoundException exc) {
 JOptionPane.showMessageDialog(null, "File not found.");
 return answerarray;
 catch(IOException exc) {
 JOptionPane.showMessageDialog(null, "Something bad happened.");
 return answerarray;
 return answerarray;
}Any pointers/tips/solutions/angry posts to tell me to stop trying to learn Java would be greatly appreciated.
Thanks in advance!
Oh, and in trying to work with it a bit further I realised I'm having a few problems with runtime errors due to exceptions. The first was due to the array being assigned out of bounds (fixed in the above code). But the second reads the following:
Exception in thread "main" java.lang.NullPointerException
 at Loadingsaving.load(CaseStudy.java:330)
 at QuizResults.(init)(CaseStudy.java.259)
 at GUI.(init)(CaseStudy.java:34)
 at CaseStudy.main(CaseStudy.java:15)Not quite sure what this one means or how to handle it. =\
Edited by: ThePermster on May 19, 2008 8:08 AM

A NullPointerException means a method has been called on a null object, or a variable that isn't pointing to any object. Your Exception points to line 330, which is:
length = s.length();A NPE on that line means that s is null. So let's look at where s is set:
if (br.readLine() == null) return answerarray;
else s = br.readLine();s gets it's value from br.readLine(), so that method must be returning null. You have a logical error here. Look at your If-Else. It reads a line, makes sure it isn't null...then it reads another line. Well what if that line is null? You are performing 2 reads here instead of 1.
Since your If condition returns a value, there's no need for an Else. The code will continue on until it reaches another return. Try this:
s = br.readLine();
if (s == null) return answerarray;

NullPointerException in persist() method

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