entitymanager_开发者

Nullpointerexception in entitymanager

hy, I\'m having trouble in using entitymanager in a java web applicaton. My code is: public class HelloWorldResource extends ServerResource {[详细]

2023-04-12 11:22 分类：问答

JPA - createEntityManagerFactory returns Null

Noob question here. I\'m following this example/tutorial to try and isolate a problem I keep getting on my main project. Problem is, the entityManagerFactory keeps returning null (thus, I get a NullPo[详细]

2023-04-12 11:07 分类：问答

Providing EntityManager by an @ConversationScoped method

I tried to run the simple JEE6 application generated by maven archetype groupId: org.fluttercode.knappsack , artifactID: jee6-sandbox-archetype in JBoss7.[详细]

2023-04-10 06:10 分类：问答

Jpa2/hibernate c3p0 pool configuration lead connection and thread leaks

I am trying to use c3p0 as connection pool provider in my application (jpa 2 and hibernate core 3.3.2)but c3p0 getting too much connection from database.This is same problem but answer not helped.I am[详细]

2023-04-09 11:38 分类：问答

retrieve from entity manager before ID is given

Here is the situation - I need to persist an object between pages.On the first page I create the object, and create a form for it.On the second page, I persist the object.The user then has an option[详细]

2023-04-05 21:26 分类：问答

ThreadLocal JPA EntityManager in DAO

In my DAO classes I have a reference to an EntityManager. I want to make the acces to the EntityManager thread-safe by using ThreadLocal.[详细]

2023-04-05 17:31 分类：问答

EntityManager.persist problem on load related entity

i have a problem with EntityManager.persist (i use tooplink of glassfish). My code is: MyEntity e = new MyEntity();[详细]

2023-04-01 06:25 分类：问答

Spring + Eclipselink + JtaTransactionManager = javax.persistence.TransactionRequiredException

I really hope you can help me. I\'ve been looking all over the internet for answers and none of them works.[详细]

2023-03-25 05:01 分类：问答

EntityManager Lifecycle when using Oracle's Virtual Private Database

I had a few questions all related to the way an entity manager is created and used in an application with respect to Virtual Private Databases, which is a feature in Oracle DB which enables Row Level[详细]

2023-03-24 03:01 分类：问答

Retrieving records from MySQL DB returns Null <Beginner question>

Question 1. I am using Netbeans 6.9.1 glassfish 3.1 . I am trying to retrieve some values from 开发者_开发百科the MySQL DB and save it on a List. My code as follows;[详细]

2023-03-23 20:30 分类：问答