I created one GWT project in eclipse.It contained the following codings
Program 1:Creategroup
package com.crimson.creategroup;
import javax.persistence.Basic;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import com.google.appengine.api.datastore.Key;
import com.google.appengine.api.users.User;
@Entity(name="CreateGroup")
public class Creategroup {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Key key;
@Basic
private User author;
@Basic
private String groupname;
@Basic
private String groupid;
@Basic
private String groupdesc;
@Basic
private String emailper;
public Key getKey() {
return key;
}
public void setAuthor(User author) {
this.author = author;
}
public User getAuthor() {
return author;
}
public void setGroupname(String groupname) {
this.groupname = groupname;
}
public String getGroupname() {
return groupname;
}
public void setGroupid(String groupid) {
this.groupid = groupid;
}
public String getGroupid() {
return groupid;
}
public void setGroupdesc(String groupdesc) {
this.groupdesc = groupdesc;
}
public String getGroupdesc() {
return groupdesc;
}
public void setEmailper(String emailper) {
this.emailper = emailper;
}
public String getEmailper() {
return emailper;
}
public Creategroup(String groupname,String groupid,String groupdesc ,String emailper) {
this.groupname = groupname;
this.groupid = groupid;
this.groupdesc = groupdesc;
this.emailper=emailper;
}
}
Program 2:Creategroupservlet
package com.crimson.creategroup;
import java.io.IOException;
import javax.persistence.EntityManager;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.google.appengine.api.users.User;
import com.google.appengine.api.users.UserService;
import com.google.appengine.api.users.UserServiceFactory;
import java.util.logging.Logger;
public class Creategroupservlet extends HttpServlet{
private static final long serialVersionUID = 1L;
private static final Logger log = Logger.getLogger(Creategroupservlet.class.getName());
public void doPost(HttpServletRequest req, HttpServletResponse resp)
throws IOException {
UserService userService = UserServiceFactory.getUserService();
User user = userService.getCurrentUser();
String groupname=req.getParameter("gname");
String groupid=req.getParameter("groupdesc");
String groupdesc=req.getParameter("gdesc");
String email=req.getParameter("eperm");
if (groupname == null) {
System.out.println("Complete all the details");
}
if (user != null) {
log.info("Greeting posted by user " + user.getNickname() + "\n " + groupname+"\n" + groupid + "\n" + groupdesc + "\n" + email);
final EntityManager em = EMF.get();
try {
Creategroup group = new Creategroup(groupname,groupid,groupdesc,email);
em.persist(group);
} finally {
em.close();
}
} else {
throw new IllegalArgumentException("anonymous posts not permitted!");
}
resp.sendRedirect("/group.jsp");
}
}
Program 3:EMF
package com.crimson.creategroup;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class EMF {
private static final EntityManagerFactory emfInstance = Persistence.createEntityManagerFactory("transactions-optional");
private EMF() {
}
public static EntityManager get() {
return emfInstance.createEntityManager();
}
}
Program 4:index.jsp
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ page import="com.google.appengine.api.users.User" %>
<%@ page import="com.google.appengine.api.users.UserService" %>
<%@ page import="com.google.appengine.api.users.UserServiceFactory" %>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<link type="text/css" rel="stylesheet" href="Group.css">
<title>Add Group into DataStore</title>
</head>
<body>
<div id="nav">
<%
UserService userService = UserServiceFactory.getUserService();
User user = userService.getCurrentUser();
if (user != null) {
response.sendRedirect("/group.jsp");
%>
<%
} else {
%>
<a href="<%= userService.createLoginURL(request.getRequestURI()) %>">Sign in</a>
<%
}
%>
</div>
<h1>Create Group</h1>
<table>
<tr>
<td colspan="2" style="font-weight:bold;">
This demo uses secured resources, so you need to be logged into your Gmail account.</td>
</tr>
</table>
</body>
</html>
program 5:group.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ page import="java.util.List" %>
<%@ page import="javax.persistence.EntityManager" %>
<%@ page import="com.google.appengine.api.users.User" %>
<%@ page import="com.google.appengine.api.users.UserService" %>
<%@ page import="com.google.appengine.api.users.UserServiceFactory" %>
<%@ page import="com.crimson.creategroup.Creategroup" %>
<%@ page import="com.crimson.creategroup.EMF" %>
<html>
<body>
<%
UserService userService = UserServiceFactory.getUserService();
User user = userService.getCurrentUser();
if (user != null) {
%>
<p>Hello, <%= user.getNickname() %>! (You can
<a href="<%= userService.createLogoutURL(request.getRequestURI()) %>">sign out</a>.)</p>
<%
} else {
response.sendRedirect("/index.jsp");
}
%>
<%
final EntityManager em = EMF.get();
try {
String query = "select from " + Creategroup.class.getName();
List<Creategroup> groups = (List<Creategroup>) em.createQuery(query).getResultList();
if (groups.isEmpty()) {
%>
<p>This table not having any group</p>
<%
} else {
for (Creategroup g : groups) {
%>
<p><b><%= g.getAuthor().getNickname() %></b> wrote:</p>
<blockquote><%= g. getGroupname() %></blockquote>
<blockquote><%= g. getGroupid() %></blockquote>
<blockquote><%= g. getGroupdesc() %></blockquote>
<blockquote><%= g. getEmailper() %></blockquote>
<%
}
}
} finally {
em.close();
}
%>
<form action="/sign" method="post">
<input type="text" name="Groupname" size="25">
<input type="text" name="Groupid" size="25">
<input type="text" name="Groupdesc" size="250">
<input type="text" name="Emaildesc" size="25">
<div><input type="submit" value="CREATE GROUP" /></div>
</form>
</body>
</html>
Program 6:Web.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app
PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.
sun.com/dtd/web-app_2_3.dtd">
<web-app>
<!-- Servlets -->
<servlet>
<servlet-name>Creategroupservlet</servlet-name>
<servlet-class>com.crimson.creategroup.Creategroupservlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Creategroupservlet</servlet-name>
<url-pattern>sign in</url-pattern>
</servlet-mapping>
<!-- Default page to serve -->
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
Program 7:persistence.xml
<?xml version="1.0" encoding="UTF-8" ?>
<persistence 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" version="1.0">
<persistence-unit name="transactions-optional">
<provider>org.datanucleus.store.appengine.jpa.DatastorePersistenceProvider</provider>
<properties>
<property name="datanucleus.NontransactionalRead" value="true"/>
<property name="datanucleus.NontransactionalWrite" value="true"/>
<property name="datanucleus.ConnectionURL" value="appengine"/>
</properties>
</persistence-unit>
</persistence
but is shows the following error
Missing required argument 'module[s]'
Google Web Toolkit 2.0.0
DevMode [-noserver] [-port port-number | "auto"] [-whitelist whitelist-string] [-blacklist blacklist-string] [-logdir directory] [-logLevel level] [-gen dir] [-codeServerPort port-number | "auto"] [-server servletContainerLauncher] [-startupUrl url] [-war dir] [-extra dir] [-workDir dir] module[s]
How to solve this thanks in advance?
