Getting "no transaction is in progress" when calling em.flush(); - spring-mvc

Question

Hi i am trying to integrate jpa with spring mvc and getting "no transaction is in progress" when trying to call flush() method.
I can make out that something is wrong with transactions even though i have used #Transactional the method is not running in a transaction.
Spring.xml
`<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context"
xmlns:jee="http://www.springframework.org/schema/jee" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">
<!-- Root Context: defines shared resources visible to all other web components -->
<context:annotation-config />
<context:component-scan base-package="com.sushant.mvc" />
<bean class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close" id="dataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://127.0.0.1/mvc" />
<property name="username" value="root" />
<property name="password" value="root" />
<property name="testOnBorrow" value="true" />
<property name="testOnReturn" value="true" />
<property name="testWhileIdle" value="true" />
<property name="timeBetweenEvictionRunsMillis" value="1800000" />
<property name="numTestsPerEvictionRun" value="3" />
<property name="minEvictableIdleTimeMillis" value="1800000" />
<property name="validationQuery" value="SELECT 1" />
<property name="maxActive" value="-1" />
<property name="maxIdle" value="-1" />
<!-- This property should be set to a value so as to support minimum 500
BC concurrent connections. For test, set this value to 5 -->
<property name="initialSize" value="5" />
</bean>
<bean class="org.springframework.orm.jpa.JpaTransactionManager"
id="transactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<tx:annotation-driven mode="proxy" transaction-manager="transactionManager"/>
<bean
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"
id="entityManagerFactory">
<property name="persistenceUnitName" value="persistenceUnit" />
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
</property>
<!-- <property name="jpaProperties">
<props>
<prop key="hibernate.hbm2ddl.auto">create</prop>
</props>
</property> -->
</bean>
<bean
class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor">
<property name="defaultPersistenceUnitName" value="persistenceUnit" />
</bean>
<!-- <bean id="user" class="com.sushant.mvc.entities.User"/> -->
</beans>
`
User.java
'
package com.sushant.mvc.entities;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.EntityManager;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.PersistenceContext;
import org.springframework.beans.factory.annotation.Configurable;
import org.springframework.stereotype.Component;
import org.springframework.transaction.annotation.Transactional;
#Entity
#Component
#Configurable
public class User {
#PersistenceContext(name = "persistenceUnit")
transient public EntityManager em;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#Column
private String userName;
#Column
private String email;
#Column
private String firstName;
#Column
private String lastName;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public static final EntityManager entityManager() {
EntityManager em = new User().em;
if (em == null)
throw new IllegalStateException(
"Entity manager has not been injected (is the Spring Aspects JAR configured as an AJC/AJDT aspects library?)");
return em;
}
#Transactional
public void save(User user) {
em.persist(user);
em.flush();
}
}
'
HomeController.java
'
package com.sushant.mvc;
import java.text.DateFormat;
import java.util.Date;
import java.util.Locale;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import com.sushant.mvc.entities.User;
/**
* Handles requests for the application home page.
*/
#Controller
public class HomeController {
#Autowired
User user;
private static final Logger logger = LoggerFactory
.getLogger(HomeController.class);
/**
* Simply selects the home view to render by returning its name.
*/
#Transactional
#RequestMapping(value = "/", method = RequestMethod.GET)
public String home(Locale locale, Model model) {
logger.info("Welcome home! the client locale is " + locale.toString());
//user.em.getTransaction().begin();
// User user=new User();
user.setEmail("sushantmahajan05#gmail.com");
user.setFirstName("Sushant");
user.setLastName("Mahajan");
user.setUserName("sushantmahajan05");
user.save(user);
User u=user.em.find(User.class, new Integer(1).longValue());
Date date = new Date();
DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.LONG,
DateFormat.LONG, locale);
String formattedDate = dateFormat.format(date);
model.addAttribute("serverTime", formattedDate);
return "home/home";
}
}
'
servlet-context.xml
'
<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/mvc"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:beans="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<!-- DispatcherServlet Context: defines this servlet's request-processing infrastructure -->
<!-- Enables the Spring MVC #Controller programming model -->
<annotation-driven />
<!-- Handles HTTP GET requests for /resources/** by efficiently serving up static resources in the ${webappRoot}/resources directory -->
<resources mapping="/resources/**" location="/resources/" />
<!-- Resolves views selected for rendering by #Controllers to .jsp resources in the /WEB-INF/views directory -->
<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<beans:property name="prefix" value="/WEB-INF/views/" />
<beans:property name="suffix" value=".jsp" />
</beans:bean>
<context:component-scan base-package="com.sushant.mvc" />
</beans:beans>
'

Answer 1

You may try creating a persistence.xml file .
You can take a look at te following example : JTASessionContext being used with JDBCTransactionFactory; auto-flush will not operate correctly with getCurrentSession()