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Communication Problem Vaading + GAE
Dears,
I have a problem with Vaadin application deployed to GAE.
After deployement end after some activities error occur:
Communication problem Take note of any unsaved data, and click here or press ESC to continue
Below please find my main Vaading class:
package com.pl.look4soft.codeanalyzer.ui;
import com.googlecode.objectify.ObjectifyService;
import com.pl.look4soft.codeanalyzer.enums.ConnectionTypesEnum;
import com.pl.look4soft.codeanalyzer.model.ConnectionData;
import com.vaadin.annotations.Theme;
import com.vaadin.annotations.Title;
import com.vaadin.annotations.VaadinServletConfiguration;
import com.vaadin.data.util.BeanItemContainer;
import com.vaadin.event.SelectionEvent;
import com.vaadin.server.VaadinRequest;
import com.vaadin.server.VaadinServlet;
import com.vaadin.ui.*;
import javax.servlet.annotation.WebServlet;
import java.util.List;
@Title("Code Analyzer")
@Theme("valo")
public class MyVaadinApplication extends UI {
Button newContact = new Button("Add new connection hh");
TextField filter = new TextField();
ConnectionForm connectionForm = new ConnectionForm();
Grid connectionList = new Grid();
@Override
public void init(VaadinRequest request) {
initComponents();
buildLayout();
}
private void initComponents(){
//ConnectionData data = new ConnectionData(1l, "sssss", "sadasd", "adsa", "dasd");
//ObjectifyService.ofy().save().entity(data).now();
newContact.addClickListener(new Button.ClickListener() {
@Override
public void buttonClick(Button.ClickEvent clickEvent) {
connectionForm.edit(new ConnectionData());
}
});
List<ConnectionData> list = ObjectifyService.ofy().load().type(ConnectionData.class).list();
connectionList.setContainerDataSource(new BeanItemContainer<>(ConnectionData.class, list));
connectionList.setColumnOrder("connectionName");
connectionList.removeColumn("id");
connectionList.setSelectionMode(Grid.SelectionMode.SINGLE);
connectionList.addSelectionListener(new SelectionEvent.SelectionListener() {
@Override
public void select(SelectionEvent selectionEvent) {
connectionForm.edit((ConnectionData) connectionList.getSelectedRow());
}
});
connectionForm.setVisible(false);
}
private void buildLayout(){
HorizontalLayout actions = new HorizontalLayout(filter, newContact);
actions.setWidth("100%");
filter.setWidth("100%");
actions.setExpandRatio(filter, 1);
VerticalLayout left = new VerticalLayout(actions, connectionList);
left.setSizeFull();
connectionList.setSizeFull();
left.setExpandRatio(connectionList, 1);
HorizontalLayout mainLayout = new HorizontalLayout(left, connectionForm);
mainLayout.setSizeFull();
mainLayout.setExpandRatio(left, 1);
// Split and allow resizing
setContent(mainLayout);
}
@WebServlet(urlPatterns = "/*", asyncSupported = true)
@VaadinServletConfiguration(ui = MyVaadinApplication.class, productionMode = false)
public static class MyUIServlet extends VaadinServlet {
}
}
And my web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
version="3.1">
<servlet>
<servlet-name>VaadinApplicationServlet</servlet-name>
<servlet-class>com.vaadin.server.VaadinServlet</servlet-class>
<init-param>
<param-name>UI</param-name>
<param-value>com.pl.look4soft.codeanalyzer.ui.MyVaadinApplication</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>VaadinApplicationServlet</servlet-name>
<url-pattern>/*</url-pattern>
</servlet-mapping>
<filter>
<filter-name>ObjectifyFilter</filter-name>
<filter-class>com.googlecode.objectify.ObjectifyFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>ObjectifyFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<listener>
<listener-class>com.pl.look4soft.codeanalyzer.dataStore.OfyHelper</listener-class>
</listener>
<session-config>
<session-timeout>60</session-timeout>
</session-config>
</web-app>
Thanks in advance.
You need to extend GAEVaadinServlet instead of VaadinServlet
Hi Artur,
Thank you very much fot your quick response.
I changed in java class and in web.xml and it works.
Is there any other issues which i should keep in mind during working with GEA and Vaadin?
Łukasz
See http://vaadin.com/download/release/7.5/7.5.6/release-notes.html