Hibernate二次学习一----------搭建Hibernate

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目录

• 1. 项目结构
  • 1.1 pom.xml
  • 1.2 hibernate.cfg.xml
  • 1.3 entity
  • 1.4 entity.hbm.xml
• 2. 测试
• 3. 总结

1. 项目结构

• 本项目使用maven进行项目管理，搭建一个简单的Hibernate框架需要四步。
• 本项目未使用注解方式进行搭建

1.1 pom.xml

• 使用maven引入依赖jar包，若未使用maven，则自己下载所需jar包放到lib目录下

<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>org.imooc</groupId>
	<artifactId>Hibernate_001</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
	</properties>

	<dependencies>
		<!-- junit -->
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>4.12</version>
			<scope>test</scope>
		</dependency>
		<!-- Hibernate -->
		<dependency>
		    <groupId>org.hibernate</groupId>
		    <artifactId>hibernate-core</artifactId>
		    <version>5.1.5.Final</version>
		</dependency>
		<!-- mysql-connector-java -->
		<dependency>
		    <groupId>mysql</groupId>
		    <artifactId>mysql-connector-java</artifactId>
		    <version>5.1.22</version>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.6.1</version>
				<configuration>
					<target>1.7</target>
					<source>1.7</source>
					<encoding>UTF-8</encoding>
				</configuration>
			</plugin>
		</plugins>
	</build>

</project>

1.2 hibernate.cfg.xml

• 在hibernate.cfg.xml中配置三方面的信息。
  • 连接数据库的信息，比如驱动、url、连接名、密码等。
  • hibernate本身的配置，比如方言、是否展示SQL，SQL格式化、建表策略等。
  • 引入映射文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
	"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
	"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>

	<session-factory>
		<!-- 数据库连接名 -->
		<property name="connection.username">root</property>
		<!-- 数据库连接密码 -->
		<property name="connection.password">20121221</property>
		<!-- 数据库驱动 -->
		<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
		<!-- 数据库连接url -->
		<property name="connection.url">
			jdbc:mysql://localhost:3306/hibernate?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8
		</property>

		<!-- 方言 -->
		<property name="dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>
		<!-- 展示SQL -->
		<property name="show_sql">true</property>
		<!-- 格式化SQL -->
		<property name="format_sql">false</property>
		<!-- 建表策略 -->
		<property name="hbm2ddl.auto">update</property>

		<!-- 指定映射文件 -->
		<mapping resource="hbm/student.hbm.xml"/>
	</session-factory>

</hibernate-configuration>

1.3 entity

• entity是实体类，对应数据库中的表结构，仅实现setter和getter方法即可

package com.imooc.hibernate.model;

import java.util.Date;

public class Student {

	private int sid; // 学号
	private String sname; // 姓名
	private String gender; // 性别
	private Date birthday; // 出生日期
	private String address; // 地址

	public Student() {
	}

	public Student(int sid, String sname, String gender, Date birthday, String address) {
		this.sid = sid;
		this.sname = sname;
		this.gender = gender;
		this.birthday = birthday;
		this.address = address;
	}

	public int getSid() {
		return sid;
	}

	public void setSid(int sid) {
		this.sid = sid;
	}

	public String getSname() {
		return sname;
	}

	public void setSname(String sname) {
		this.sname = sname;
	}

	public String getGender() {
		return gender;
	}

	public void setGender(String gender) {
		this.gender = gender;
	}

	public Date getBirthday() {
		return birthday;
	}

	public void setBirthday(Date birthday) {
		this.birthday = birthday;
	}

	public String getAddress() {
		return address;
	}

	public void setAddress(String address) {
		this.address = address;
	}

	@Override
	public String toString() {
		return "Student [sid=" + sid + ", sname=" + sname + ", gender="
				+ gender + ", birthday=" + birthday + ", address=" + address + "]";
	}

}

1.4 entity.hbm.xml

• entity.hbm.xml是映射文件，将数据库表与entity进行对应

<?xml version="1.0" encoding="UTF-8"?>
<!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="com.imooc.hibernate.model.Student">
		<id name="sid" type="int">
			<column name="SID"/>
			<generator class="assigned"/> <!-- 主键生成策略 -->
		</id>
		<property name="sname" type="java.lang.String">
			<column name="SNAME"/>
		</property>
		<property name="gender" type="java.lang.String">
			<column name="GENDER"></column>
		</property>
		<property name="birthday" type="java.util.Date">
			<column name="BIRTHDAY"/>
		</property>
		<property name="address" type="java.lang.String">
			<column name="ADDRESS"></column>
		</property>
	</class>

</hibernate-mapping>

2. 测试

• 使用junit进行测试

package com.imooc.hibernate.test;

import java.util.Date;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import com.imooc.hibernate.model.Student;

public class StudentTest {

	private SessionFactory sessionFactory;
	private Session session;
	private Transaction transaction;

	@Test
	public void testSaveStudent() {

		// 生成学生对象
		Student s = new Student(3, "张三丰", "男", new Date(), "武当山");
		session.save(s);

	}

	@Before
	public void init() {

		// 创建会话工厂对象
		sessionFactory = new Configuration().configure().buildSessionFactory();
		// 创建会话对象
		session = sessionFactory.openSession();
		// 开始事务
		transaction = session.beginTransaction();

	}

	@After
	public void destory () {

		// 提交事务
		transaction.commit();
		// 关闭会话
		session.close();
		// 关闭会话工厂
		sessionFactory.close();

	}

}

3. 总结

Hibernate初步搭建很简单，主要是使用hibernate.cfg.xml进行数据库连接的配置，使用entity.hbm.xml进行数据库表结构与实体类进行映射。

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参考：Hibernate初探之单表映射

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