【Spring】SpringMVC整合JPA

妖狐艹你老母 2022-08-22 00:24 150阅读 0赞

这篇文章是在SpringMVC的基础上对数据持久层JPA的整合，实现了应用层和数据库的数据交互。在整合JPA前，请先参照下面第一篇博文搭建好SpringMVC框架。

## 一. 和本篇博文相关的一些基础知识请参考下面几篇博文： ##

1.  SpringMVC框架的搭建和配置详解请参考：[**http://blog.csdn.net/jianyuerensheng/article/details/51258942**][http_blog.csdn.net_jianyuerensheng_article_details_51258942]。
2.  JPA的ORM框架原理介绍请参考：[**http://blog.csdn.net/jianyuerensheng/article/details/50804360**][http_blog.csdn.net_jianyuerensheng_article_details_50804360]。
3.  JPA生命周期、映射关系详解请参考：[**http://blog.csdn.net/jianyuerensheng/article/details/50819155**][http_blog.csdn.net_jianyuerensheng_article_details_50819155]。

## 二.JAP的配置过程： ##

项目整体结构如下：  
![这里写图片描述][20160509122439310]  
![这里写图片描述][20160509122600624]  
**1.在web.xml文件中进行配置**

<context-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath*:META-INF/spring/applicationContext*.xml</param-value>
        </context-param>
        
        <filter>
            <filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
            <filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
        </filter>
        <filter-mapping>
            <filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
            <url-pattern>/*</url-pattern>
        </filter-mapping>

**2. 添加Spring上下文配置文件applicationContext.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" xmlns:jpa="http://www.springframework.org/schema/data/jpa" xmlns:task="http://www.springframework.org/schema/task" xsi:schemaLocation="http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd 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/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.1.xsd ">
    
        <context:component-scan base-package="com.zjn.service" />
    
        <bean id="configProperties" class="org.springframework.beans.factory.config.PropertiesFactoryBean">
            <property name="locations">
                <list>
                    <value>classpath*:META-INF/spring/*.properties</value>
                </list>
            </property>
        </bean>
    
        <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PreferencesPlaceholderConfigurer">
            <property name="properties" ref="configProperties"></property>
        </bean>
    
        
        <bean class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor" />
    
        
        <bean class="org.springframework.orm.jpa.JpaTransactionManager" id="transactionManager">
            <property name="entityManagerFactory" ref="entityManagerFactory" />
        </bean>
        
        <bean id="jpaVendorAdapter" class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
            <property name="showSql" value="true" />
            <property name="database" value="${database}" />
            <property name="databasePlatform" value="org.hibernate.dialect.MySQLMyISAMDialect" />
        </bean>
        
        <bean class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean" id="entityManagerFactory">
            <property name="persistenceUnitName" value="persistenceUnit" />
            <property name="dataSource" ref="dataSource" />
            <property name="jpaVendorAdapter" ref="jpaVendorAdapter" />
        </bean>
    
        <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
            <property name="driverClassName" value="${database.driverClassName}" />
            <property name="url" value="${database.url}" />
            <property name="username" value="${database.username}" />
            <property name="password" value="${database.password}" />
            <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="defaultAutoCommit" value="false" />
        </bean>
    
        
        <jpa:repositories base-package="com.zjn.repository" entity-manager-factory-ref="entityManagerFactory"></jpa:repositories>
    </beans>

**3. 添加JPA配置文件 persistence.xml。**

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
    <persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
        <persistence-unit name="persistenceUnit" transaction-type="RESOURCE_LOCAL">
            <properties>
                <property name="hibernate.jdbc.batch_size" value="30" />
                <property name="hibernate.use_sql_comments" value="true" />
                
                <property name="hibernate.hbm2ddl.auto" value="update" />
                <property name="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy" />
                <property name="hibernate.connection.charSet" value="UTF-8" />
            </properties>
        </persistence-unit>
    </persistence>

**4. 数据库配置文件 database.properties**

database=MYSQL
    database.url=jdbc:mysql://localhost:3306/spring?zeroDateTimeBehavior=convertToNull&characterEncoding=UTF-8&characterSetResults=UTF-8
    database.username=root
    database.password=smit0296139
    database.driverClassName=com.mysql.jdbc.Driver

**5.UserRepository.java**

package com.zjn.repository;
    
    import java.util.List;
    
    import org.springframework.data.jpa.repository.JpaRepository;
    import org.springframework.data.jpa.repository.Query;
    import org.springframework.data.repository.query.Param;
    
    import com.zjn.entity.User;
    
    public interface UserRepository extends JpaRepository<User, Long> {
    
        @Query("select u from User u where id = :id")
        public User findById(@Param("id") Long id);
    
        @Query("select u from User u ")
        public List<User> findAlls();
    
        @Query("select count(id) from User u ")
        public Long countId();
    
    }

**6.UserController.java**

package com.zjn.controller;
    
    import java.util.List;
    
    import javax.annotation.Resource;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.web.bind.annotation.ModelAttribute;
    import org.springframework.web.bind.annotation.RequestMapping;
    
    import com.zjn.entity.User;
    import com.zjn.repository.UserRepository;
    
    /** * 用户管理 * * @author zjn */
    @Controller
    public class UserController {
        @Autowired
        UserRepository userRepository;
        @RequestMapping("")
        public String Create(Model model) {
            return "create";
        }
    
        @RequestMapping("/save")
        public String Save(@ModelAttribute("form") User user, Model model) { // user:视图层传给控制层的表单对象；model：控制层返回给视图层的对象
            User user2 = userRepository.saveAndFlush(user);
            model.addAttribute("user", user2);
            return "detail";
        }
    }

**7.运行结果**  
初始化界面：  
![这里写图片描述][20160509124238288]  
输入内容：  
![这里写图片描述][20160509124310992]  
点击创建运行结果：  
![这里写图片描述][20160509124324024]

[http_blog.csdn.net_jianyuerensheng_article_details_51258942]: http://blog.csdn.net/jianyuerensheng/article/details/51258942
[http_blog.csdn.net_jianyuerensheng_article_details_50804360]: http://blog.csdn.net/jianyuerensheng/article/details/50804360
[http_blog.csdn.net_jianyuerensheng_article_details_50819155]: http://blog.csdn.net/jianyuerensheng/article/details/50819155
[20160509122439310]: /images/20220724/ca3550e92aa64076b3c43ddce595bb91.png
[20160509122600624]: /images/20220724/367f0e1f1a8b4819af2ab51c9b4af757.png
[20160509124238288]: /images/20220724/f1f762962aa943b2a68cbfeb08fa7679.png
[20160509124310992]: /images/20220724/c5d8394edd8849c6ac14de0682f0f378.png
[20160509124324024]: /images/20220724/ab1c900044b7482eb1c73279f7f6fab9.png