Hibernate的关键API详解以及上手第一个Hibernate项目
在 Java 中使用 Hibernate 的步骤
开始 Hibernate 开发
上手第一个 Hibernate 项目
新建项目
打开 MyEclipse，新建一个 Web 项目
项目名称为 hibernate ，配置使用默认（Java8、Java EE8、JSTL1.2.4），点击 finish 完成即可。
集成 struts2
在 pom.xml 加上 struts2 的依赖，我们使用 struts2 的新版本 struts2.5.30
<!-- struts2 -->
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-core</artifactId>
<version>2.5.30</version>
</dependency>
web.xml 加上对应的过滤器
<web-app 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_3_0.xsd"
version="3.0">
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>
注意，上面是类似 struts2.3 的方法，其实还有更新的配置方法，下面的配置方法也可以：
<web-app 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_3_0.xsd"
version="3.0">
<filter>
<filter-name>struts-prepare</filter-name>
<filter-class>org.apache.struts2.dispatcher.filter.StrutsPrepareFilter</filter-class>
</filter>
<filter>
<filter-name>struts-execute</filter-name>
<filter-class>org.apache.struts2.dispatcher.filter.StrutsExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts-prepare</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter-mapping>
<filter-name>struts-execute</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>
新建一个 struts.xml 文件
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.5//EN"
"http://struts.apache.org/dtds/struts-2.5.dtd">
<struts>
<package name="hibernate" extends="struts-default">
</package>
</struts>
集成 Hibernate5
我们使用最新版本 Hibernate5.6.14.Final 。
pom.xml 文件加上 hibernate 所需依赖
<!-- hibernate -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>5.6.14.Final</version>
</dependency>
新增 hibernate.cfg.xml 文件
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property>
<property name="connection.username">terwer</property>
<property name="connection.password">123456</property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="dialect">org.hibernate.dialect.MySQL57Dialect</property>
<property name="show_sql">true</property>
<!-- DB schema will be updated if needed -->
<property name="hibernate.hbm2ddl.auto">update</property>
<!-- mapping -->
<mapping resource="space/terwer/model/Person.hbm.xml"/>
</session-factory>
</hibernate-configuration>
创建持久化类
在 space.terwer.model 包下面新建一个 model
Person.java
package space.terwer.model;
import java.util.Date;
/**
* 人员
*
* @author terwer
* @name Person
* @date 2023-01-03 00:40
**/
public class Person {
private Integer id;
private String name;
private String password;
private Integer age;
private Date registerDate;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Date getRegisterDate() {
return registerDate;
}
public void setRegisterDate(Date registerDate) {
this.registerDate = registerDate;
}
}
SessionFactory 接口
Session 接口
DTD
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd" >
<hibernate-mapping>
</hibernate-mapping>
Model 文件映射
person.hbm.xml
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="space.terwer.model.Person" table="person">
<id name="id" column="id" type="integer">
<generator class="increment"/>
</id>
<property name="username" column="username" type="string"/>
<property name="password" column="password" type="string"/>
<property name="age" column="age" type="integer"/>
<property name="registerDate" column="registerDate" type="java.util.Date"/>
</class>
</hibernate-mapping>
Hibernate 操作工具类
HibernateUtil.java
/**
* Hibernate工具类
*
* @author terwer
* @name HibernateUtil
* @date 2023-01-03 01:03
**/
public class HibernateUtil {
private static SessionFactory sessionFactory;
static {
try {
sessionFactory = new Configuration().configure().buildSessionFactory();
} catch (Exception e) {
e.printStackTrace();
}
}
public static Session openSession() {
return sessionFactory.openSession();
}
public static void closeSession(Session session) {
if (null != session) {
session.close();
}
}
}
Dao 层实现
/**
* PersonDAO实现类
*
* @author terwer
* @name PersonDAOImpl
* @date 2023-01-03 01:02
**/
public class PersonDAOImpl implements IPersonDAO {
@Override
public void savePerson(Person person) {
Session session = HibernateUtil.openSession();
Transaction tx = session.beginTransaction();
try {
session.save(person);
tx.commit();
} catch (Exception e) {
if (null != tx) {
tx.rollback();
}
throw e;
} finally {
HibernateUtil.closeSession(session);
}
}
}
Service 层实现
public class PersonServiceImpl implements IPersonService {
@Override
public void savePerson(Person person) {
IPersonDAO personDAO = new PersonDAOImpl();
personDAO.savePerson(person);
}
}
Action 层实现
PersonAction.java
/**
* 人员处理
*
* @author terwer
* @name PersonAction
* @date 2023-01-03 00:55
**/
public class PersonAction extends ActionSupport {
private String username;
private String password;
private Integer age;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String savePerson() throws Exception {
Person person = new Person();
person.setUsername(username);
person.setPassword(password);
person.setAge(age);
person.setRegisterDate(new Date());
IPersonService personService = new PersonServiceImpl();
personService.savePerson(person);
return SUCCESS;
}
}
页面入口
register.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>register</title>
</head>
<body>
<form action="savePerson.action">
username:<input type="text" name="username" size="20"/><br/>
password:<input type="text" name="password" size="20"/><br/>
age:<input type="text" name="age"/><br/>
<input type="submit" value="submit"/>
</form>
</body>
</html>
运行结果
145 [main] INFO org.eclipse.jetty.util.log - Logging initialized @273ms to org.eclipse.jetty.util.log.Slf4jLog
WARNING: jetty-runner is deprecated.
See Jetty Documentation for startup options
https://www.eclipse.org/jetty/documentation/
174 [main] INFO org.eclipse.jetty.runner.Runner - Runner
323 [main] INFO org.eclipse.jetty.server.Server - jetty-9.4.46.v20220331; built: 2022-03-31T16:38:08.030Z; git: bc17a0369a11ecf40bb92c839b9ef0a8ac50ea18; jvm 1.8.0_333-b02
Connected to the target VM, address: '127.0.0.1:64891', transport: 'socket'
760 [main] INFO o.e.j.a.AnnotationConfiguration - Scanning elapsed time=297ms
868 [main] INFO org.eclipse.jetty.server.session - DefaultSessionIdManager workerName=node0
868 [main] INFO org.eclipse.jetty.server.session - No SessionScavenger set, using defaults
871 [main] INFO org.eclipse.jetty.server.session - node0 Scavenging every 600000ms
1413 [main] INFO o.e.j.server.handler.ContextHandler - Started o.e.j.w.WebAppContext@6a6cb05c{/hibernate-idea,file:///Users/terwer/Documents/workspace/senior-java-engineer-road/p7-skill/framework/hibernate/hibernate-idea/src/main/webapp/,AVAILABLE}{file:///Users/terwer/Documents/workspace/senior-java-engineer-road/p7-skill/framework/hibernate/hibernate-idea/src/main/webapp/}
1433 [main] INFO o.e.jetty.server.AbstractConnector - Started ServerConnector@158d2680{HTTP/1.1, (http/1.1)}{0.0.0.0:8080}
1433 [main] INFO org.eclipse.jetty.server.Server - Started @1565ms
8768 [qtp1318180415-33] INFO org.hibernate.Version - HHH000412: Hibernate ORM core version 5.6.14.Final
9106 [qtp1318180415-33] INFO o.h.annotations.common.Version - HCANN000001: Hibernate Commons Annotations {5.1.2.Final}
9624 [qtp1318180415-33] WARN o.hibernate.orm.connections.pooling - HHH10001002: Using Hibernate built-in connection pool (not for production use!)
9633 [qtp1318180415-33] INFO o.hibernate.orm.connections.pooling - HHH10001005: using driver [com.mysql.jdbc.Driver] at URL [jdbc:mysql://localhost:3306/hibernate]
9634 [qtp1318180415-33] INFO o.hibernate.orm.connections.pooling - HHH10001001: Connection properties: {user=terwer, password=****}
9634 [qtp1318180415-33] INFO o.hibernate.orm.connections.pooling - HHH10001003: Autocommit mode: false
9638 [qtp1318180415-33] INFO o.h.e.j.c.i.DriverManagerConnectionProviderImpl - HHH000115: Hibernate connection pool size: 20 (min=1)
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
10125 [qtp1318180415-33] INFO org.hibernate.dialect.Dialect - HHH000400: Using dialect: org.hibernate.dialect.MySQL57Dialect
10655 [qtp1318180415-33] INFO o.hibernate.orm.connections.access - HHH10001501: Connection obtained from JdbcConnectionAccess [org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator$ConnectionProviderJdbcConnectionAccess@4e90008] for (non-JTA) DDL execution was not in auto-commit mode; the Connection 'local transaction' will be committed and the Connection will be set into auto-commit mode.
10700 [qtp1318180415-33] INFO o.h.e.t.j.p.i.JtaPlatformInitiator - HHH000490: Using JtaPlatform implementation: [org.hibernate.engine.transaction.jta.platform.internal.NoJtaPlatform]
Hibernate: select max(id) from person
Hibernate: insert into person (username, password, age, registerDate, id) values (?, ?, ?, ?, ?)
使用 IDEA 上手第一个 Hibernate 项目
请参考 003.使用IDEA搭建Struts2-5项目 。
在 IDEA 中，如果 struts-default 提示不出来，可能需要以下步骤：
1、安装 Struts2 插件
2、选择 Project Structure -> 新增 Facets ，选择 Struts 2 ，把对应的 xml 文件加进去
