Exception while dispatching incoming RPC call

2010-10-04 Thread kuoy...@taiwan
Hi:
I using GWT but it get a error(I want to GWT with JPA) :
[WARN] Exception while dispatching incoming RPC call
com.google.gwt.user.server.rpc.UnexpectedException: Service method
'public abstract void
org.kuoying.client.GreetingService.save(org.kuoying.client.RpcItem)'
threw an unexpected exception: java.lang.NullPointerException
at
com.google.gwt.user.server.rpc.RPC.encodeResponseForFailure(RPC.java:
378)
..

souce code:

public class First implements EntryPoint {
/**
 * This is the entry point method.
 */
public void onModuleLoad() {
Button sendButton = new Button(Send);
final TextBox nameField = new TextBox();
nameField.setText(GWT User);
RootPanel.get(nameFieldContainer).add(nameField);
RootPanel.get(sendButtonContainer).add(sendButton);
sendButton.addClickHandler(new ClickHandler(){
public void onClick(ClickEvent event) {
GreetingServiceAsync greetingService = GWT
.create(GreetingService.class);

String textToServer = nameField.getText();
RpcItem ri = new RpcItem();
ri.setId(7);
ri.setUsername(textToServer);
greetingService.save(ri, new AsyncCallback() {
public void onFailure(Throwable caught) 
{
Window.alert(Fail);
}
public void onSuccess(Object result) {
Window.alert(Success);
}
});
}
});
}
}
--
@RemoteServiceRelativePath(greet)
public interface GreetingService extends RemoteService {
//  String greetServer(String name) throws IllegalArgumentException;
void save(RpcItem ri);
}
--
public interface GreetingServiceAsync {
void save(RpcItem ri, AsyncCallback callback);
}

public class GreetingServiceImpl extends RemoteServiceServlet
implements
GreetingService {

private static final long serialVersionUID = 1L;

@Override
public void save(RpcItem ri) {
EntityManagerFactory emf;
EntityManager em = null;
try {
emf = Persistence.createEntityManagerFactory(oo);
em = emf.createEntityManager();
em.getTransaction().begin();
em.persist(ri);
em.getTransaction().commit();
} finally {
em.close();
}
}
}



What can I do?? THX^^

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Exception while dispatching incoming RPC call

2010-10-04 Thread kuoy...@taiwan
Hi:
I using GWT but it get a error(I want to GWT with JPA) :
[WARN] Exception while dispatching incoming RPC call
com.google.gwt.user.server.rpc.UnexpectedException: Service method
'public abstract void
org.kuoying.client.GreetingService.save(org.kuoying.client.RpcItem)'
threw an unexpected exception: java.lang.NullPointerException
at
com.google.gwt.user.server.rpc.RPC.encodeResponseForFailure(RPC.java:
378)
..

souce code:

public class First implements EntryPoint {
/**
 * This is the entry point method.
 */
public void onModuleLoad() {
Button sendButton = new Button(Send);
final TextBox nameField = new TextBox();
nameField.setText(GWT User);
RootPanel.get(nameFieldContainer).add(nameField);
RootPanel.get(sendButtonContainer).add(sendButton);
sendButton.addClickHandler(new ClickHandler(){
public void onClick(ClickEvent event) {
GreetingServiceAsync greetingService = GWT
.create(GreetingService.class);

String textToServer = nameField.getText();
RpcItem ri = new RpcItem();
ri.setId(7);
ri.setUsername(textToServer);
greetingService.save(ri, new AsyncCallback() {
public void onFailure(Throwable caught) 
{
Window.alert(Fail);
}
public void onSuccess(Object result) {
Window.alert(Success);
}
});
}
});
}
}
--
@RemoteServiceRelativePath(greet)
public interface GreetingService extends RemoteService {
//  String greetServer(String name) throws IllegalArgumentException;
void save(RpcItem ri);
}
--
public interface GreetingServiceAsync {
void save(RpcItem ri, AsyncCallback callback);
}

public class GreetingServiceImpl extends RemoteServiceServlet
implements
GreetingService {

private static final long serialVersionUID = 1L;

@Override
public void save(RpcItem ri) {
EntityManagerFactory emf;
EntityManager em = null;
try {
emf = Persistence.createEntityManagerFactory(oo);
em = emf.createEntityManager();
em.getTransaction().begin();
em.persist(ri);
em.getTransaction().commit();
} finally {
em.close();
}
}
}



What can I do?? THX^^

-- 
You received this message because you are subscribed to the Google Groups 
Google Web Toolkit group.
To post to this group, send email to google-web-tool...@googlegroups.com.
To unsubscribe from this group, send email to 
google-web-toolkit+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/google-web-toolkit?hl=en.