Dear all, I am getting NullPointerException in the following code for the transaction tx. Please reply me soon.
Code: package com.wissen.enterprisebysush. server; import java.util.List; import javax.jdo.JDOHelper; import javax.jdo.PersistenceManager; import javax.jdo.PersistenceManagerFactory; import javax.jdo.Transaction; import javax.persistence.EntityManager; import javax.persistence.EntityManagerFactory; import javax.persistence.EntityTransaction; import javax.persistence.Persistence; import javax.persistence.Query; import com.google.gwt.user.client.Window; import com.google.gwt.user.server.rpc.RemoteServiceServlet; import com.wissen.enterprisebysush.client.GreetingService; import com.wissen.enterprisebysush.server.domainobject.Department; import com.wissen.enterprisebysush.server.domainobject.Employee; /** * The server side implementation of the RPC service. */ @SuppressWarnings("serial") public class GreetingServiceImpl extends RemoteServiceServlet implements GreetingService { EntityManagerFactory emf = Persistence.createEntityManagerFactory("transactions-optional"); public String greetServer(String input) { String serverInfo = getServletContext().getServerInfo(); String userAgent = getThreadLocalRequest().getHeader("User-Agent"); return "Hello, " + input + "!<br><br>I am running " + serverInfo + ".<br><br>It looks like you are using:<br>" + userAgent; } @SuppressWarnings("unchecked") public void addDept(String dept_name, String dept_head) { EntityManager em = null; try { em = emf.createEntityManager(); em.getTransaction().begin(); Department d = new Department(); d.setDept_name(dept_name); d.setHead(dept_head); Query q = em.createQuery("select from com.wissen.enterprisebysush.server.domainobject.Department d"); List<Department> deptList = q.getResultList(); for (Department dept : deptList) { System.out.println("Department name: " + dept.getDept_name()); } em.persist(d); } finally { em.getTransaction().commit(); em.close(); } } public void addEmp(String emp_name, String emp_sal, String did) { EntityManager em = emf.createEntityManager(); try { String s = did; EntityTransaction transaction = em.getTransaction(); transaction.begin(); System.out.println("value of Department_name is::" + s); System.out.println("Transaction is active and is::"+transaction); // Query q = em.createQuery("select dept_id from com.wissen.enterprisebysush.server.domainobject.Department d where d.dept_name = ?1"); // q.setParameter(1, s); // System.out.println("Name of Department is::" + s); // Department dept = (Department) q.getSingleResult(); Query q = em.createQuery("select from com.wissen.enterprisebysush.server.domainobject.Department d"); Department dept = (Department) q.getResultList().get(0); System.out.println("Name of Department is::" + dept.getDept_name()); //System.out.println("Query executed Successfully!!!!!!!!!!!!!!" + q.getSingleResult()); Employee e = new Employee(); e.setEmp_name("Ritesh Navandar"); e.setEmp_sal("5000"); e.setDepartment(dept); em.persist(e); System.out.println("Transaction: " + transaction); transaction.commit(); em.close(); } catch (NullPointerException e) { e.printStackTrace(); System.out.println("Exception::" + e.getCause()); } finally { } } } -- Regards, Sujata... -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.