Spring的MVC / JPA。 从数据库中提取数据后没有结果

Question

I'm new to web development. I'm trying to create very simple application using spring-mvc, jpa/hibrenate, oracle db and tomcat v7.0 server. App will just pull some data and display on page. The problem is when i'm trying to pull data there is no result on page. I have no clue what i'm doing wrong.

Entity class.

@Entity
@Table(name="Product")
public class Product {

@Id
@Column(name="productId")
private String productId;

@Column(name="name")
private String name;

@Column(name="unitPrice")
private int unitPrice;

@Column(name="description")
private String description;

@Column(name="manufacturer")
private String manufacturer;

@Column(name="category")
private String category;

@Column(name="unitsInStock")
private int unitsInStock;

@Column(name="unitsInOrder")
private long unitsInOrder;

@Column(name="condition")
private String condition;

//constructors getters and setters

.xml file with config

 <?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:mvc="http://www.springframework.org/schema/mvc"
 xmlns:jdbc="http://www.springframework.org/schema/jdbc"
 xmlns:aop="http://www.springframework.org/schema/aop"
 xmlns:jpa="http://www.springframework.org/schema/data/jpa"        
 xmlns:repository="http://www.springframework.org/schema/data/repository"
 xsi:schemaLocation="http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd
 http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
 http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
 http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.1.xsd
 http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.8.xsd
 http://www.springframework.org/schema/data/repository http://www.springframework.org/schema/data/repository/spring-repository-1.11.xsd">

<mvc:annotation-driven />

<context:component-scan base-package="com.packt.webstore" />

<bean
    class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="prefix" value="/WEB-INF/views/" />
    <property name="suffix" value=".jsp" />
</bean>

<bean id="dataSource" class="oracle.jdbc.pool.OracleDataSource">
    <property name="URL" value="jdbc:oracle:thin:@localhost:1521:orcl" />
    <property name="user" value="crossing" />
    <property name="password" value="123" />
</bean>

<bean id="hibernateJpaVendorAdapter" 
    class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"/>

<bean id="entityManagerFactory"        
 class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
 <property name="dataSource" ref="dataSource" />
 <property name="persistenceUnitName" value="persistence-webstore" />
</bean>

<bean id="transactionManager" 
    class="org.springframework.orm.jpa.JpaTransactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>

</beans>

persistence.xml

<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="1.0">
<persistence-unit name="persistence-webstore"
    transaction-type="RESOURCE_LOCAL">
    <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
    <properties>
        <property name="hibernate.dialect"value="org.hibernate.dialect.Oracle10gDialect" />
        <property name="hibernate.hbm2ddl.auto" value="create-drop" />
        <property name="hibernate.connection.driver_class" value="oracle.jdbc.OracleDriver" />
        <property name="hibernate.connection.username" value="crossing" />
        <property name="hibernate.connection.password" value="123" />
        <property name="hibernate.connection.url" value="jdbc:oracle:thin:@localhost:1521:orcl" />
        <property name="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy" />
        <property name="hibernate.connection.charSet" value="UTF-8" />
    </properties>
</persistence-unit>
</persistence>

Service class

@Service
public class ProductService {
  @PersistenceContext
  private EntityManager em;

  @Transactional
  public List<Product> getAll() {
    List<Product> result = new ArrayList<Product>();
    result = em.createQuery("SELECT e FROM Product e", Product.class)
            .getResultList();

    return result;

  }
}

My .jsp file

//....
<c:forEach items="${products}" var="product">
            <div class="col-sm-6 col-md-3" style="padding-bottom: 15px">
                <div class="thumbnail">
                    <div class="caption">                           
                            <h3>${product.name}</h3>
                            <p>${product.description}</p>
                            <p>${product.unitPrice}PLN</p>
                            <p>Units in stock: ${product.unitsInStock}</p>
                    </div>
                </div>
            </div>
</c:forEach>
//..

And controller

@Controller
public class ProductController {
  @Autowired
  public ProductService proService;

  @RequestMapping("/")
  public String list(Model model) {

    model.addAttribute("products", proService.findAll());

    return "products";
  }

}

** EDIT **

I've made some changes

Added ProductRepository

public interface ProductRepository extends Repository<Product, String>{

   public List<Product> findAll();  

}

Changed Service class

@Service
public class ProductService implements ProductRepository{

@PersistenceContext
private EntityManager em;

@Override
@Transactional
public List<Product> findAll() {

   EntityManagerFactory factory = Persistence
                .createEntityManagerFactory("persistence-webstore"); 
   em = factory.createEntityManager();

   List<Product> listPersons = em.createQuery("SELECT p FROM Product p",Product.class).getResultList();

   if (listPersons.isEmpty()) {
       System.out.println("List contains no data");
   }         

   return listPersons;
}

No NPE this time or any other error, just still i can't get those elements on list. There must be something with my query or configuration, I dunno.

Edit
Hibernate show_sql result is down below, but why is it looks in that way? Is this supposed to be?

Hibernate: 
select
    product0_.productId as productId1_0_,
    product0_.category as category2_0_,
    product0_.condition as condition3_0_,
    product0_.description as description4_0_,
    product0_.manufacturer as manufacturer5_0_,
    product0_.name as name6_0_,
    product0_.unitPrice as unitPrice7_0_,
    product0_.unitsInOrder as unitsInOrder8_0_,
    product0_.unitsInStock as unitsInStock9_0_ 
from
    Product product0_

** EDIT **

Finally works. To my surprise just simple update maven project helped.

Answer 1

ravius,

I think you need to add repository class.

repository

public interface DocumentRepository extends PagingAndSortingRepository<Document, Integer> {

}

service - > daoImpl

@Override
public List<Document> findAllDocument() {
    return documentRepository.findAll();
}

.xml

<jpa:repositories base-package="com.test.faas.repositoryex"
    entity-manager-factory-ref="entityManagerFactory"></jpa:repositories>


<bean id="entityManagerFactory"
    class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
    <property name="jpaVendorAdapter">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
    </property>
    <property name="dataSource" ref="dataSource" />
    <property name="jpaProperties">
        <props>
            <!-- <prop key="hibernate.dialect">org.hibernate.dialect.DerbyDialect</prop> 
                <prop key="hibernate.default_schema">test</prop> -->

            <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>


            <prop key="hibernate.connection.pool_size">4</prop>
            <prop key="hibernate.connection.shutdown">true</prop>
            <prop key="hibernate.show_sql">true</prop>

            <prop key="hibernate.hbm2ddl.auto">update</prop>

            <!-- <prop key="hibernate.hbm2ddl.auto">create</prop> <prop key="hibernate.ddl_auto">auto</prop> -->
        </props>
    </property>

    <!-- entity define class package -->
    <property name="packagesToScan" value="com.text.faas.dtoex" />

</bean>

You trying to work.

If not work.

I need you error message.