Java 没有 Spring Boot 的 Spring Data JPA
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原文地址: http://stackoverflow.com/questions/23974249/
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Spring Data JPA without Spring Boot
提问by quarks
Spring Boot doesn't work with Google App Engine (at least not for me).
Spring Boot 不适用于 Google App Engine（至少不适用于我）。
However much of the examples written or available in the GitHubor other repositories are using Spring Boot, is there any example for Spring-Data-JPA that does not use Spring Boot and use plain context XML as before?
然而，在GitHub或其他存储库中编写或可用的大部分示例都使用 Spring Boot，是否有任何 Spring-Data-JPA 示例不使用 Spring Boot 并像以前一样使用纯上下文 XML？
That will show
那会显示
- spring/context.xml (or servlet-context.xml)
- spring/context.xml (或servlet-context.xml)
回答by JM Yang
Just created this example for you:
刚刚为您创建了这个示例：
src/main/webapp/WEB-INF/spring/context.xml
src/main/webapp/WEB-INF/spring/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:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:jpa="http://www.springframework.org/schema/data/jpa"
xsi:schemaLocation="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.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">
<context:property-placeholder location="/WEB-INF/spring/jdbc.properties" />
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
p:driverClassName="${jdbc.driverClassName}" p:url="${jdbc.url}"
p:username="${jdbc.username}" p:password="${jdbc.password}" />
<bean id="hibernateJpaVendorAdapter"
class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
<!-- Configure the entity manager factory bean -->
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter" ref="hibernateJpaVendorAdapter" />
<!-- Set JPA properties -->
<property name="jpaProperties">
<props>
<prop key="hibernate.dialect">${hibernate.dialect}</prop>
</props>
</property>
<property name="packagesToScan" value="com.demo.data" />
</bean>
<!-- Configure the transaction manager bean -->
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<tx:annotation-driven />
<jpa:repositories base-package="com.demo.data" />
<context:component-scan base-package="com.demo.svc" />
</beans>
/src/main/webapp/WEB-INF/spring/jdbc.properties
/src/main/webapp/WEB-INF/spring/jdbc.properties
# JDBC Connection
jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://host:3306/db
jdbc.username=user
jdbc.password=password
hibernate.dialect=org.hibernate.dialect.MySQLDialect
/src/main/webapp/WEB-INF/spring/servlet-context.xml
/src/main/webapp/WEB-INF/spring/servlet-context.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/mvc"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:beans="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.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.xsd">
<context:component-scan base-package="com.demo.web" />
</beans:beans>
web.xml
网页.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
version="2.5">
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/context.xml</param-value>
</context-param>
<context-param>
<param-name>webAppRootKey</param-name>
<param-value>demo_jpa</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<servlet>
<servlet-name>appServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/servlet-context.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>appServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
pom.xml
pom.xml
<properties>
<org.springframework-version>4.1.7.RELEASE</org.springframework-version>
<org.hibernate-em-version>4.3.8.Final</org.hibernate-em-version>
<org.springframework.data-version>1.9.0.RELEASE</org.springframework.data-version>
<dbcp-version>1.4</dbcp-version>
<mysql-connector-version>5.1.28</mysql-connector-version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${org.springframework-version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${org.springframework-version}</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>${org.springframework.data-version}</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>${org.hibernate-em-version}</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql-connector-version}</version>
</dependency>
<dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>${dbcp-version}</version>
</dependency>
</dependencies>
Data Entity: com.demo.data.User
数据实体：com.demo.data.User
package com.demo.data;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name = "SYS_USERS")
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "USER_ID")
private int id;
@Column(name = "USER_NAME")
private String name;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Spring Data JPA Repository: com.demo.data.UserRepository
Spring Data JPA 存储库：com.demo.data.UserRepository
package com.demo.data;
import org.springframework.data.repository.CrudRepository;
public interface UserRepository extends CrudRepository<User, Integer> {
}
Service
服务
Interface:
界面：
package com.demo.svc;
import com.demo.data.User;
public interface UserService {
User findUserById(Integer id);
}
Implementation:
执行：
package com.demo.svc;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.demo.data.User;
import com.demo.data.UserRepository;
@Service
public class UserServiceImpl implements UserService {
@Autowired
UserRepository userRepository;
public User findUserById(Integer id) {
return userRepository.findOne(id);
}
}
Web Controller: com.demo.web.UserController
网页控制器：com.demo.web.UserController
package com.demo.web;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import com.demo.svc.UserService;
@Controller
public class UserController {
@Autowired
UserService svc;
@RequestMapping("/")
@ResponseBody
public String test() {
return svc.findUserById(1).getName();
}
}
回答by MindFlayerA
This is happening because you haven't created the bean of UserRepository in context. There are a number of ways you can do this since you're not using a spring boot project so it won't make an object in the container at startup due to which @Autowired is not injecting the object in the UserRepository class. For this project, you can update the following in your project:
发生这种情况是因为您尚未在上下文中创建 UserRepository 的 bean。有多种方法可以执行此操作，因为您没有使用 Spring Boot 项目，因此它不会在启动时在容器中创建对象，因为 @Autowired 没有在 UserRepository 类中注入对象。对于此项目，您可以更新项目中的以下内容：
package com.demo.svc;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.demo.data.User;
import com.demo.data.UserRepository;
@Service
public class UserServiceImpl implements UserService {
UserRepository userRepository;
public User findUserById(Integer id) {
return userRepository.findOne(id);
}
public UserRepository setRepo(UserRepository repo)
{
userRepository=repo;
}
}
Also, you'll need to inject the object from the container. In src/main/webapp/WEB-INF/spring/context.xml
此外，您还需要从容器中注入对象。在 src/main/webapp/WEB-INF/spring/context.xml
<bean id="repo" class="com.demo.data.UserRepository"></bean>
<!--Setting the object ref in com.demo.svc.UserServiceImpl-->
<bean id="userserviceImpl" class="com.demo.svc.UserServiceImpl">
<property name="userRepository" ref="repo"></property>
</bean>
Hope it helps
希望能帮助到你
