前言
译文链接:http://websystique.com/spring/spring4-hibernate4-mysql-maven-integration-example-using-annotations/
本文将基于注解配置, 集成Spring 4和Hibernate 4,开发一个增删改查应用,涉及以下内容:
- 创建Hibernate实体
- 保存数据到mysql数据库中
- 在事务
transaction内部执行增删改查操作 - 典型企业应用中不同层之间的交互
- 基于注解配置
当然,我们也会给出XML配置作为对比。
如果你的应用是基于Spring MVC开发,那么可以参考该链接:Spring4 MVC Hibernate and MySQL integration.
涉及的技术及开发工具
- Spring 4.0.6.RELEASE
- Hibernate Core 4.3.6.Final
- MySQL Server 5.6
- Joda-time 2.3
- Maven 3
- JDK 1.6
- Eclipse JUNO Service Release 2
工程结构目录

步骤一:往pom.xml中添加依赖
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.websystique.spring</groupId>
<artifactId>Spring4HibernateExample</artifactId>
<version>1.0.0</version>
<packaging>jar</packaging>
<name>Spring4HibernateExample</name>
<properties>
<springframework.version>4.0.6.RELEASE</springframework.version>
<hibernate.version>4.3.6.Final</hibernate.version>
<mysql.connector.version>5.1.31</mysql.connector.version>
<joda-time.version>2.3</joda-time.version>
</properties>
<dependencies>
<!-- Spring -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${springframework.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${springframework.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${springframework.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>${springframework.version}</version>
</dependency>
<!-- Hibernate -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>${hibernate.version}</version>
</dependency>
<!-- MySQL -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql.connector.version}</version>
</dependency>
<!-- Joda-Time -->
<dependency>
<groupId>joda-time</groupId>
<artifactId>joda-time</artifactId>
<version>${joda-time.version}</version>
</dependency>
<!-- To map JodaTime with database type -->
<dependency>
<groupId>org.jadira.usertype</groupId>
<artifactId>usertype.core</artifactId>
<version>3.0.0.CR1</version>
</dependency>
</dependencies>
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.2</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
很明显我们需要添加Spring、Hibernate和Mysql连接器相关依赖,另外,由于我们使用了joda-time库来处理时间,所以也引入了joda-time依赖。usertype-core库引入是为了提供数据库时间类型与joda-time LocalDate之间的映射。
步骤二:配置Hibernate
com.websystique.spring.configuration.HibernateConfiguration
package com.websystique.spring.configuration;
import java.util.Properties;
import javax.sql.DataSource;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.Environment;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.hibernate4.HibernateTransactionManager;
import org.springframework.orm.hibernate4.LocalSessionFactoryBean;
import org.springframework.transaction.annotation.EnableTransactionManagement;
@Configuration
@EnableTransactionManagement
@ComponentScan({ "com.websystique.spring.configuration" })
@PropertySource(value = { "classpath:application.properties" })
public class HibernateConfiguration {
@Autowired
private Environment environment;
@Bean
public LocalSessionFactoryBean sessionFactory() {
LocalSessionFactoryBean sessionFactory = new LocalSessionFactoryBean();
sessionFactory.setDataSource(dataSource());
sessionFactory.setPackagesToScan(new String[] { "com.websystique.spring.model" });
sessionFactory.setHibernateProperties(hibernateProperties());
return sessionFactory;
}
@Bean
public DataSource dataSource() {
DriverManagerDataSource dataSource = new DriverManagerDataSource();
dataSource.setDriverClassName(environment.getRequiredProperty("jdbc.driverClassName"));
dataSource.setUrl(environment.getRequiredProperty("jdbc.url"));
dataSource.setUsername(environment.getRequiredProperty("jdbc.username"));
dataSource.setPassword(environment.getRequiredProperty("jdbc.password"));
return dataSource;
}
private Properties hibernateProperties() {
Properties properties = new Properties();
properties.put("hibernate.dialect", environment.getRequiredProperty("hibernate.dialect"));
properties.put("hibernate.show_sql", environment.getRequiredProperty("hibernate.show_sql"));
properties.put("hibernate.format_sql", environment.getRequiredProperty("hibernate.format_sql"));
return properties;
}
@Bean
@Autowired
public HibernateTransactionManager transactionManager(SessionFactory s) {
HibernateTransactionManager txManager = new HibernateTransactionManager();
txManager.setSessionFactory(s);
return txManager;
}
}
@Configuration注解表明该类包含了用@Bean标注的方法,这些被@Bean标注的方法可以生成bean并交由spring容器管理,在这里例子中,这个类代表了hibernate的配置。
@ComponentScan注解与xml配置中的“context:component-scan base-package="..."”等价,提供了扫描bean的包路径。
@EnableTransactionManagement注解与xml配置中Spring的tx:*命名空间等价,主要用于开启基于注解的事务管理。
@PropertySource注解用于在Spring运行时Environment中声明一组属性(在应用classpath路径下的properties文件中定义),可根据不同环境灵活改变属性值。
sessionFactory()方法创建了一个LocalSessionFactoryBean,与基于XML的配置类似,我们需要一个数据源dataSource和hibernate配置文件(如hibernate.properties)。
多亏了@PropertySource注解,我们可以从.properties文件中得到具体属性值,使用Spring的Environment接口获取对应项目的配置值。
一旦创建了SessionFactory,该bean将会被注入到transactionManager方法中,最终对sessionFactory创建的sessions提供事务支持功能。
如下是本文使用的属性配置文件:
/src/main/resources/application.properties
jdbc.driverClassName = com.mysql.jdbc.Driver
jdbc.url = jdbc:mysql://localhost:3306/websystique
jdbc.username = myuser
jdbc.password = mypassword
hibernate.dialect = org.hibernate.dialect.MySQLDialect
hibernate.show_sql = false
hibernate.format_sql = false
另外,对应的基于XML配置如下
<?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:tx="http://www.springframework.org/schema/tx"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.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-4.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd">
<context:property-placeholder location="classpath:application.properties" />
<context:component-scan base-package="com.websystique.spring" />
<tx:annotation-driven transaction-manager="transactionManager"/>
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${jdbc.driverClassName}" />
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}"/>
</bean>
<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean" >
<property name="dataSource" ref="dataSource"/>
<property name="packagesToScan">
<list>
<value>com.websystique.spring.model</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">${hibernate.dialect}</prop>
<prop key="hibernate.show_sql">${hibernate.show_sql:false}</prop>
<prop key="hibernate.format_sql">${hibernate.format_sql:false}</prop>
</props>
</property>
</bean>
<bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<bean id="persistenceExceptionTranslationPostProcessor"
class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>
</beans>
步骤三:Spring配置
com.websystique.spring.configuration.AppConfig
package com.websystique.spring.configuration;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
@Configuration
@ComponentScan(basePackages = "com.websystique.spring")
public class AppConfig {
}
在我们这个示例中,即使该配置类内部是空的,但是使用了@ComponentScan注解,可以自动检测到对应包下所有的beans。
其实你可以完全去除以上的配置,将bean扫描功能放在application context级别去实现(main方法里)。
在成熟的应用里,你会发现使用配置类配置beans(如messageSource、PropertySourcesPlaceHolderConfigurer...)非常方便。
对应的基于XML的配置
<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"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">
<context:component-scan base-package="com.websystique.spring" />
</beans>
以上就是关于本工程的所有配置了,现在,为了让工程能跑起来,我们还需要添加service、dao层,实体对象,数据库。
步骤四:DAO层
com.websystique.spring.dao.AbstractDao
package com.websystique.spring.dao;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
public abstract class AbstractDao {
@Autowired
private SessionFactory sessionFactory;
protected Session getSession() {
return sessionFactory.getCurrentSession();
}
public void persist(Object entity) {
getSession().persist(entity);
}
public void delete(Object entity) {
getSession().delete(entity);
}
}
注意,我们在步骤二创建的SessionFactory会被自动装配到这里,这个类将作为基类用于执行数据库相关操作。
com.websystique.spring.dao.EmployeeDao
package com.websystique.spring.dao;
import java.util.List;
import com.websystique.spring.model.Employee;
public interface EmployeeDao {
void saveEmployee(Employee employee);
List<Employee> findAllEmployees();
void deleteEmployeeBySsn(String ssn);
Employee findBySsn(String ssn);
void updateEmployee(Employee employee);
}
com.websystique.spring.dao.EmployeeDaoImpl
package com.websystique.spring.dao;
import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.Query;
import org.hibernate.criterion.Restrictions;
import org.springframework.stereotype.Repository;
import com.websystique.spring.model.Employee;
@Repository("employeeDao")
public class EmployeeDaoImpl extends AbstractDao implements EmployeeDao{
public void saveEmployee(Employee employee) {
persist(employee);
}
@SuppressWarnings("unchecked")
public List<Employee> findAllEmployees() {
Criteria criteria = getSession().createCriteria(Employee.class);
return (List<Employee>) criteria.list();
}
public void deleteEmployeeBySsn(String ssn) {
Query query = getSession().createSQLQuery("delete from Employee where ssn = :ssn");
query.setString("ssn", ssn);
query.executeUpdate();
}
public Employee findBySsn(String ssn){
Criteria criteria = getSession().createCriteria(Employee.class);
criteria.add(Restrictions.eq("ssn",ssn));
return (Employee) criteria.uniqueResult();
}
public void updateEmployee(Employee employee){
getSession().update(employee);
}
}
步骤五:添加Service层代码
com.websystique.spring.service.EmployeeService
package com.websystique.spring.service;
import java.util.List;
import com.websystique.spring.model.Employee;
public interface EmployeeService {
void saveEmployee(Employee employee);
List<Employee> findAllEmployees();
void deleteEmployeeBySsn(String ssn);
Employee findBySsn(String ssn);
void updateEmployee(Employee employee);
}
com.websystique.spring.service.EmployeeServiceImpl
package com.websystique.spring.service;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import com.websystique.spring.dao.EmployeeDao;
import com.websystique.spring.model.Employee;
@Service("employeeService")
@Transactional
public class EmployeeServiceImpl implements EmployeeService{
@Autowired
private EmployeeDao dao;
public void saveEmployee(Employee employee) {
dao.saveEmployee(employee);
}
public List<Employee> findAllEmployees() {
return dao.findAllEmployees();
}
public void deleteEmployeeBySsn(String ssn) {
dao.deleteEmployeeBySsn(ssn);
}
public Employee findBySsn(String ssn) {
return dao.findBySsn(ssn);
}
public void updateEmployee(Employee employee){
dao.updateEmployee(employee);
}
}
以上比较引人注目的部分是@Transactional注解,配置了该注解的类会在每个类方法开启事务,并在方法结束的时候提交事务(或者在方法内部出错时回滚事务)。
注意,由于以上事务范围是方法级别的,我们在方法内部使用DAO,DAO方法会在同样的事物内部执行。
步骤六:创建实体类(POJO)
com.websystique.spring.model.Employee
package com.websystique.spring.model;
import java.math.BigDecimal;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import org.hibernate.annotations.Type;
import org.joda.time.LocalDate;
@Entity
@Table(name="EMPLOYEE")
public class Employee {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
@Column(name = "NAME", nullable = false)
private String name;
@Column(name = "JOINING_DATE", nullable = false)
@Type(type="org.jadira.usertype.dateandtime.joda.PersistentLocalDate")
private LocalDate joiningDate;
@Column(name = "SALARY", nullable = false)
private BigDecimal salary;
@Column(name = "SSN", unique=true, nullable = false)
private String ssn;
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;
}
public LocalDate getJoiningDate() {
return joiningDate;
}
public void setJoiningDate(LocalDate joiningDate) {
this.joiningDate = joiningDate;
}
public BigDecimal getSalary() {
return salary;
}
public void setSalary(BigDecimal salary) {
this.salary = salary;
}
public String getSsn() {
return ssn;
}
public void setSsn(String ssn) {
this.ssn = ssn;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + id;
result = prime * result + ((ssn == null) ? 0 : ssn.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (!(obj instanceof Employee))
return false;
Employee other = (Employee) obj;
if (id != other.id)
return false;
if (ssn == null) {
if (other.ssn != null)
return false;
} else if (!ssn.equals(other.ssn))
return false;
return true;
}
@Override
public String toString() {
return "Employee [id=" + id + ", name=" + name + ", joiningDate="
+ joiningDate + ", salary=" + salary + ", ssn=" + ssn + "]";
}
}
这是一个标准的实体类,基于JPA注解@Entity, @Table, @Column以及hibernate注解@Type(用于提供数据库类型与Joda-Time LocalDate的映射)。
步骤七:在数据库里创建Schema
CREATE TABLE EMPLOYEE(
id INT NOT NULL auto_increment,
name VARCHAR(50) NOT NULL,
joining_date DATE NOT NULL,
salary DOUBLE NOT NULL,
ssn VARCHAR(30) NOT NULL UNIQUE,
PRIMARY KEY (id)
);
步骤八:创建main方法执行程序
package com.websystique.spring;
import java.math.BigDecimal;
import java.util.List;
import org.joda.time.LocalDate;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;
import com.websystique.spring.configuration.AppConfig;
import com.websystique.spring.model.Employee;
import com.websystique.spring.service.EmployeeService;
public class AppMain {
public static void main(String args[]) {
AbstractApplicationContext context = new AnnotationConfigApplicationContext(AppConfig.class);
EmployeeService service = (EmployeeService) context.getBean("employeeService");
/*
* Create Employee1
*/
Employee employee1 = new Employee();
employee1.setName("Han Yenn");
employee1.setJoiningDate(new LocalDate(2010, 10, 10));
employee1.setSalary(new BigDecimal(10000));
employee1.setSsn("ssn00000001");
/*
* Create Employee2
*/
Employee employee2 = new Employee();
employee2.setName("Dan Thomas");
employee2.setJoiningDate(new LocalDate(2012, 11, 11));
employee2.setSalary(new BigDecimal(20000));
employee2.setSsn("ssn00000002");
/*
* Persist both Employees
*/
service.saveEmployee(employee1);
service.saveEmployee(employee2);
/*
* Get all employees list from database
*/
List<Employee> employees = service.findAllEmployees();
for (Employee emp : employees) {
System.out.println(emp);
}
/*
* delete an employee
*/
service.deleteEmployeeBySsn("ssn00000002");
/*
* update an employee
*/
Employee employee = service.findBySsn("ssn00000001");
employee.setSalary(new BigDecimal(50000));
service.updateEmployee(employee);
/*
* Get all employees list from database
*/
List<Employee> employeeList = service.findAllEmployees();
for (Employee emp : employeeList) {
System.out.println(emp);
}
context.close();
}
}
注意,假如你想删除AppConfig文件,那么只需将
AbstractApplicationContext context = new AnnotationConfigApplicationContext(AppConfig.class);
替换为
AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
context.scan("com.websystique.spring");
context.refresh();
Employee [id=1, name=Han Yenn, joiningDate=2010-10-10, salary=10000, ssn=ssn00000001]
Employee [id=2, name=Dan Thomas, joiningDate=2012-11-11, salary=20000, ssn=ssn00000002]
Employee [id=1, name=Han Yenn, joiningDate=2010-10-10, salary=50000, ssn=ssn00000001]
工程代码
http://websystique.com/?smd_process_download=1&download_id=802
注:源码EmployeeDaoImpl类中有一处错误,将26行表名Employee改成EMPLOYEE即可。
本文介绍如何使用Spring4和Hibernate4集成开发一个简单的增删改查应用,并使用Maven进行项目管理。涵盖基于注解配置的事务管理、不同层间的交互等内容。
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