help on @Transactional in TX

[ligerdave]

im getting this error

Exception in thread "main" java.lang.ClassCastException: $Proxy17 cannot be cast to com.*********.database.service.StoryService
	at com.*********.test.Main.main(Main.java:28)

here is my context xml

<bean id="sessionFactory"
		class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"
		p:dataSource-ref="dataSource" p:hibernateProperties-ref="hibernateProperties"
		p:annotatedClasses-ref="hibernatePojoModelClasses" />

	<bean id="transactionManager"
		class="org.springframework.orm.hibernate3.HibernateTransactionManager"
		p:sessionFactory-ref="sessionFactory" />

	<tx:annotation-driven transaction-manager="transactionManager" />

	<bean id="storyDao" class="com.*********.database.dao.StoryDao">
		<constructor-arg ref="sessionFactory" />
	</bean>


	<bean id="storyService" class="com.*********.database.service.StoryService"
		p:storyDao-ref="storyDao" />

and here is my service class

	@Transactional(readOnly = true)
	public Set<Story> findUserStory(User user) {

		return null;
	}

and last, this is my test class

StoryService storyS = (StoryService) context.getBean("storyService");

looks like everything is in place, like the example in the book.

help plz!

[chudak]

StoryService needs to be an interface not a class. Your StoryService bean should implement the StoryService interface.

[ligerdave]

thank you for the reply! i will try it out.


but why tho? w/o having the annotation, it was totally fine

[chudak]

Because the annotation adds a transactional wrapper (proxy) around your class. The wrapper can implement an interface but it cannot extend a class. When you try and pass it as an argument where a class type is expected you will get a class cast exception. When you pass it as an argument where an interface is expected, it will work.

If you aren't defining interfaces for you services, you should be. How are you testing the collaborators that use them?

[ligerdave]

gotta ya! thank you so much again for explaining that

[ligerdave]

chudak,

i tried w/ the interface and still getting this

Exception in thread "main" java.lang.ClassCastException: $Proxy24 cannot be cast to

really confused

[chudak]

Post your code and configuration...

[ligerdave]

context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
	xmlns:tx="http://www.springframework.org/schema/tx" xmlns:p="http://www.springframework.org/schema/p"
	xmlns:aop="http://www.springframework.org/schema/aop" xmlns:util="http://www.springframework.org/schema/util"
	xsi:schemaLocation="
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-2.5.xsd">


	


	<!-- LISTS -->
	<util:list id="hibernatePojoModelClasses">
		<value>com.test.database.model.Vote</value>
		<value>com.test.database.model.Picture</value>
		<value>com.test.database.model.User</value>
	</util:list>

	<util:properties id="hibernateProperties">
		<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</prop>
		<prop key="hibernate.hbm2ddl.auto">update</prop>
		<prop key="show_sql">true</prop>
		<prop key="hibernate.c3p0.minPoolSize">5</prop>
		<prop key="hibernate.c3p0.maxPoolSize">20</prop>
		<prop key="hibernate.c3p0.timeout">600</prop>
		<prop key="hibernate.c3p0.max_statement">50</prop>
		<prop key="hibernate.format_sql">true</prop>
		<prop key="hibernate.generate_statistics">true</prop>
	</util:properties>

	<!-- DATA SOURCE -->
	<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
		destroy-method="close" p:driverClassName="com.mysql.jdbc.Driver"

		p:url="jdbc:mysql://localhost:3306/test" p:username="test"
		p:password="****" p:removeAbandoned="true" p:removeAbandonedTimeout="60"
		p:maxActive="100" p:maxIdle="30" p:maxWait="-1" />


	<bean id="sessionFactory"
		class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"
		p:dataSource-ref="dataSource" p:hibernateProperties-ref="hibernateProperties"
		p:annotatedClasses-ref="hibernatePojoModelClasses" />

	<bean id="transactionManager"
		class="org.springframework.orm.hibernate3.HibernateTransactionManager"
		p:sessionFactory-ref="sessionFactory" />

	<tx:annotation-driven transaction-manager="transactionManager" />


	<!-- DAOs -->
	<bean id="userDao" class="com.test.database.dao.UserDao">
		<constructor-arg ref="sessionFactory" />
	</bean>
	<bean id="pictureDao" class="com.test.database.dao.PictureDao">
		<constructor-arg ref="sessionFactory" />
	</bean>
	<bean id="voteDao" class="com.test.database.dao.VoteDao">
		<constructor-arg ref="sessionFactory" />
	</bean>

	<!-- SERVICEs -->
	<!--
		<bean id="pictureService"
		class="com.test.database.service.PictureService"
		p:pictureDao-ref="pictureDao" />
	-->

	<bean id="userService" class="com.test.database.service.UserService"
		p:userDao-ref="userDao" />
	<bean id="voteService" class="com.test.database.service.VoteService"
		p:voteDao-ref="voteDao" />


</beans>

interface

public interface IUserService {

	public User register(User user);

	public User findUserById(String id);

	@Transactional
	public User findUserByEmail(String email);

	public User login(String email, String password);

}

implement

public class UserService implements IUserService, UserDaoIoC {

	private UserDao dao;

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * com.test.database.service.IUserService#findUserByEmail(java.lang.
	 * String)
	 */
	public User findUserByEmail(String email) {

		List<?> users = this.dao.findByNamedQuery("user.findByEmail", "email",
				email);

		if (users.size() > 0) {
			return (User) users.get(0);
		} else {
			return null;
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * com.test.database.service.IUserService#findUserById(java.lang.String)
	 */
	public User findUserById(String id) {
		// TODO Auto-generated method stub
		return null;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see com.test.database.service.IUserService#login(java.lang.String,
	 * java.lang.String)
	 */
	public User login(String email, String password) {
		// TODO Auto-generated method stub
		return null;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * com.test.database.service.IUserService#register(com.test.database
	 * .model.User)
	 */
	public User register(User user) {

		this.dao.save(user);
		return user;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * com.test.ioc.database.dao.UserDaoIoC#setUserDao(com.test.database
	 * .dao.UserDao)
	 */
	public void setUserDao(UserDao dao) {
		this.dao = dao;

	}

}

testing

public class Main {

	/**
	 * 
	 */
	public Main() {
		// TODO Auto-generated constructor stub
	}

	/**
	 * @param args
	 */
	public static void main(String[] args) {

		ApplicationContext context = new ClassPathXmlApplicationContext(
				"applicationContext.xml");

		UserService us = (UserService) context.getBean("userService");

		
		
		System.out.println(us.findUserByEmail("test@test.com").getMemberSince());
		
	}

}

[chudak]

You are still trying to cast the bean to it's CLASS...you need to cast it to it's INTERFACE:

IUserService us = (IUserService) context.getBean("userService");

Program to INTERFACES not IMPLEMENTATIONS...

[ligerdave]

hah you are right. forgot to change in the testing class

thank you so much man!