Question

我想使用 Spring MVC 和 Hibernate 创建一个包含CRUD逻辑的简单网页。我创建了这个简单的UserController：

我的春季配置[上]：

<?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:p="http://www.springframework.org/schema/p"
    xmlns:c="http://www.springframework.org/schema/c"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">

    <!-- Root Context: defines shared resources visible to all other web components -->
    <context:annotation-config />
    <context:component-scan base-package="org.vdzundza.dao" />
    <context:component-scan base-package="org.vdzundza.service" />

    <bean id="propertiesConfig"
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"
        p:location="/WEB-INF/jdbc.properties" />

    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
        destroy-method="close">
        <property name="driverClassName" value="${jdbc.driverClassName}" />
        <property name="url" value="${jdbc.url}" />
        <property name="username" value="${jdbc.username}" />
        <property name="password" value="${jdbc.password}" />
    </bean>

    <bean id="sessionFactory"
        class="org.springframework.orm.hibernate4.LocalSessionFactoryBean"
        lazy-init="true">
        <property name="dataSource" ref="dataSource" />
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</prop>
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
                <prop key="hibernate.current_session_context_class">thread</prop> 
            </props>
        </property>
        <property name="packagesToScan" value="org.vdzundza.beans" />
    </bean>
<tx:annotation-driven/>
    <bean id="transactionManager"
        class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory"><ref local="sessionFactory"/></property>
    </bean>
</beans>

我的控制器：

package org.vdzundza.web;

import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.vdzundza.beans.User;
import org.vdzundza.service.UserService;

@Controller
@RequestMapping("/user")
public class UserController {

    @Autowired
    private UserService userService;

    private static final Logger logger = LoggerFactory
            .getLogger(UserController.class);    

    @RequestMapping(value = "/edit/{id}", method = RequestMethod.GET)
    public String updateUserGet(Map<String, Object> map, @PathVariable("id") Long id){
        User user = userService.loadUser(id);
        map.put("user", user);
        return "edit";
    }

    @RequestMapping(value = "/edit", method = RequestMethod.POST)
    public String updateUserPost(@ModelAttribute("user") User user, BindingResult result){
        logger.info("update user: " + user.toString());
        userService.updateUser(user);
        return "redirect:/user/index";
    }
}

我的UserDAO：

package org.vdzundza.dao;

import java.util.List;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;
import org.vdzundza.beans.User;

@Repository
@Transactional(value = "transactionManager")
public class UserDAOImpl implements UserDao {

    @Autowired
    private SessionFactory sessionFactory;

    private static final Logger logger = LoggerFactory
            .getLogger(UserDAOImpl.class);


    public void updateUser(User user) {
        Session session = sessionFactory.getCurrentSession();
        Transaction tx = null;
        try {
            tx = session.beginTransaction();
            session.update(user);
            tx.commit();

        } catch (RuntimeException e) {
            tx.rollback();
        }
    }

    public User loadUser(Long id) {
        Session session = sessionFactory.openSession();
        return (User) session.load(User.class, id);
    }
}

和服务：

package org.vdzundza.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import org.vdzundza.beans.User;
import org.vdzundza.dao.UserDao;

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserDao userDAO;        

    @Transactional
    public void updateUser(User user) {
        userDAO.updateUser(user);

    }

    @Transactional
    public User loadUser(Long id) {
        return userDAO.loadUser(id);
    }
}

我更新的简单表单：

<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Update user</title>
</head>
<body>
    <form:form method="post"
        action="${pageContext.request.contextPath}/user/edit"
        commandName="user">
        <table>
            <tr>
                <td><form:label path="firstName">First Name</form:label></td>
                <td><form:input path="firstName" /></td>
            </tr>

            <tr>
                <td><form:label path="lastName">Last Name</form:label></td>
                <td><form:input path="lastName" /></td>
            </tr>

            <tr>
                <td><form:label path="network">network</form:label></td>
                <td><form:input path="network" /></td>
            </tr>
            <tr>
                <td colspan="2"><input type="submit" value="update user" /></td>
            </tr>

        </table>
    </form:form>
</body>
</html>

为什么我的“updateUser”（dao）方法不更新实体？

Answer 1

做一个

session.flush();

之后

tx.commit();

刷新机制的目标是将会话中持久对象的状态与数据库同步。

如果更改对象的状态，则状态不会反映在数据库中。在flush hibernate上，将数据库与对象的新状态同步。

Answer 2

我将隐藏元素添加到表单中。

<form:hidden path="id"/>

实体未在Hibernate中更新

2 个答案: