状态: 感谢回答，但没有人回答重要标签描述以反射(reflect)我给出的简单代码。 (13 年 7 月 20 日)
我已经阅读了很多教程，但每件事都混在一起，或者只是作为一个看起来很小或抽象的特定示例。
我真的无法让某些事情在我的脑海中变得合乎逻辑。可能是我用具体的实际代码学习。
问题:任何人都可以展示如何使以下不完整的代码完全工作与 spring 3.x 和 hibernate 4。 x.
重要:
我想，即使在这个简单的例子中， sessionfactory 和 hibernate 查询数据库 在 Service 类中(在大型应用程序中设置边界 Service 类使用许多 DAO 并一次提交事务)
我忘记了我是在哪里读到它的，也许是在 spring 文档中——但它清楚地说，不要把 @Transactional 放在你的 DAO 上 :P 所以一般来说，您的服务层是您定义事务边界的地方。 服务方法通常是一大块东西，如果全部通过，则提交，否则失败并回滚 这当然可能不是一个顽固的规则，但它是我们构建企业资源规划网络核心的方式。 我忘了我是在哪里读到它的，也许是在 spring 文档中——但它清楚地说，不要把 @Transactional 放在你的 DAO 上
例如 http://blog.patouchas.net/technology/hibernate-dao-java-tutorial/就像没有 Spring 一样？
注释 缺失或不正确。正确的注释应该是什么。
这些类是否有具体的 spring.xml(除了通常的)？如果可行，我只想使用注释。正确的注解，如@component、service、repository、resource、autowired
我通常是这样获取交易的
Configuration configuration = new Configuration();
configuration.configure();
ServiceRegistry serviceRegistry = new ServiceRegistryBuilder()
.applySettings(configuration.getProperties())
.buildServiceRegistry();
SessionFactory sessionFactory = configuration.buildSessionFactory(serviceRegistry);
Session session = sessionFactory.openSession();
session.beginTransaction();
session.getTransaction().commit();
session.close();
春暖花开
@Controller
public class UserController {
private IUserService userService;
@RequestMapping("/users")
public String creatUser(){
Users user = new Users();
user.setEmail("myemail@mydomain.com");
user.setName("myname");
userService.creatUser(user);
return "user-creation-result";
}
}
public class UserService implements IUserService{
private IUserDAO userDAO;
public void creatUser(Users user){
//what to do here
//how to call the sessionfactory
//and call it in a way that each call
// gives the same instance
userDAO.creatUser(user);
}
}
public class UserDAO implements IUserDAO{
public void creatUser(Users user){
// what to do here?
}
}
不过这不会那么重要。
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">org.postgresql.Driver</property>
<property name="connection.url">jdbc:postgresql://localhost:5432/postgres</property>
<property name="connection.username">postgres</property>
<property name="connection.password">abc</property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.PostgreSQLDialect</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">create</property>
<!-- Names the annotated entity class -->
<mapping class="taskmanagsetup.Boards" />
<mapping class="taskmanagsetup.BoardPrivileges" />
<mapping class="taskmanagsetup.Boxes" />
<mapping class="taskmanagsetup.BoxPrivileges" />
<mapping class="taskmanagsetup.Groups" />
<mapping class="taskmanagsetup.Tasks" />
<mapping class="taskmanagsetup.TaskPrivileges" />
<mapping class="taskmanagsetup.Users" />
</session-factory>
</hibernate-configuration>
@Entity
public class Users {
@Id
@GeneratedValue
private long id;
@ManyToMany
private Collection<Groups> groupList = new ArrayList<Groups>();
private String type; // admin / teamlead / normal
private String name;
private String email;
private String password;
@Lob
private String description;
private boolean isEnabled;
/**
* @return the id
*/
public long getId() {
return id;
}
/**
* @param id the id to set
*/
public void setId(long id) {
this.id = id;
}
/**
* @return the groupdId
*/
/**
* @param groupdId the groupdId to set
*/
/**
* @return the type
*/
public String getType() {
return type;
}
/**
* @param type the type to set
*/
public void setType(String type) {
this.type = type;
}
/**
* @return the name
*/
public String getName() {
return name;
}
/**
* @param name the name to set
*/
public void setName(String name) {
this.name = name;
}
/**
* @return the email
*/
public String getEmail() {
return email;
}
/**
* @param email the email to set
*/
public void setEmail(String email) {
this.email = email;
}
/**
* @return the password
*/
public String getPassword() {
return password;
}
/**
* @param password the password to set
*/
public void setPassword(String password) {
this.password = password;
}
/**
* @return the isEnabled
*/
public boolean isIsEnabled() {
return isEnabled;
}
/**
* @param isEnabled the isEnabled to set
*/
public void setIsEnabled(boolean isEnabled) {
this.isEnabled = isEnabled;
}
/**
* @return the groupList
*/
public Collection<Groups> getGroupList() {
return groupList;
}
/**
* @param groupList the groupList to set
*/
public void setGroupList(Collection<Groups> groupList) {
this.groupList = groupList;
}
/**
* @return the description
*/
public String getDescription() {
return description;
}
/**
* @param description the description to set
*/
public void setDescription(String description) {
this.description = description;
}
}
最佳答案
如果您使用的是 Spring 3.x 和 Hibernate 4.x，您可以考虑 three-tier application architecture :
数据层
您可以为常见的 DAO 方法创建一个抽象基类。
public abstract class AbstractDAO<E extends Serializable,
PK extends Serializable> {
private final transient Class<E> entityClass;
public AbstractDAO(final Class<E> entityClass) {
this.entityClass = entityClass;
}
protected abstract EntityManager getEntityManager();
public final E find(final PK id) {
return getEntityManager().find(entityClass, id);
}
// Another common methods
}
在每个 DAO 实现中，您可以为该 DAO 放置特定的方法。
@Repository
public final class UserDAO extends AbstractDAO<User, Long> {
@Autowired
private transient EntityManagerFactory emf;
public UserDAO() {
super(User.class);
}
@Override
protected EntityManager getEntityManager() {
return emf.createEntityManager();
}
// particular methods for this DAO
}
应用层
如果用户不存在怎么办？将此逻辑放在这一层中。
@Service
public final class UserService {
private static final Logger LOG = LoggerFactory.getLogger(UserService.class);
@Autowired
private transient UserDAO userDAO;
public User findUser(final Long id) {
return userDAO.find(id);
}
}
表示层
@Controller
@RequestMapping("/user")
public final class UserController {
private static final Logger LOG = LoggerFactory
.getLogger(UserController.class);
@Autowired
private transient UserService userService;
@RequestMapping(value = "/find/{id}", method = RequestMethod.GET)
public void downloadImage(
@PathVariable("id") final Long id,
final HttpServletResponse response) throws IOException {
//
}
}
web.xml，其中包含应用程序配置和调度程序配置:
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<display-name>MyWebApp</display-name>
<!-- log4j -->
<context-param>
<param-name>log4jConfigLocation</param-name>
<param-value>classpath:log4j.xml</param-value>
</context-param>
<context-param>
<param-name>webAppRootKey</param-name>
<param-value>MyWebApp.root</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
<!-- Spring -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<servlet>
<servlet-name>dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<!-- Welcome -->
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
dispatcher-servlet.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans ···>
<context:component-scan base-package="···.mywebapp" use-default-filters="false">
<context:include-filter expression="org.springframework.stereotype.Controller" type="annotation"/>
</context:component-scan>
<mvc:annotation-driven />
</beans>
如果你想避免 persistence.xml 文件，你可以将它放在你的 applicationContext.xml 中:
<?xml version="1.0" encoding="UTF-8"?>
<beans ···>
<bean id="dataSource" class="···">
<property name="URL" value="···" />
<property name="user" value="···" />
<property name="password" value="···" />
</bean>
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean" p:dataSource-ref="dataSource" p:packagesToScan="···.model">
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" p:showSql="false" p:databasePlatform="org.hibernate.dialect.SQLServerDialect" />
</property>
<property name="jpaProperties">
<props>
<prop key="hibernate.format_sql">true</prop>
</props>
</property>
</bean>
<context:component-scan base-package="···.mywebapp" use-default-filters="false">
<context:include-filter expression="org.springframework.stereotype.Repository" type="annotation"/>
<context:include-filter expression="org.springframework.stereotype.Service" type="annotation"/>
</context:component-scan>
</beans>
希望对您有所帮助。
关于java - View 、DAO、服务和 Controller 的基本 Hibernate 和 Spring MVC 集成，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/17736568/