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Hibernate学习之类级别注解
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类级别注解：
1. @Entity 实体：表示映射实体类，使用@Entity时必须指定实体类的主键属性
@Entity(name="")
name：可选，对应数据库中的一张表。若表名与实体名相同则可省略
2. @Table 表：表示实体类对应的数据库表的信息
@Table(name="", catalog="", schema="")
name：可选，映射表的名称，默认表名与实体名称一致，只有在不一致的情况下才需指定表名
catalog：可选，表示目录名称，默认为Catalog("")
schema：可选，表示模式名称，默认为Schema("")
3. @Embeddable 嵌入类：表示一个非Entity类可以嵌入到一个Entity类中作为属性而存在
实例
1.项目结构
2.pom.xml
<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.hibernate</groupId>
<artifactId>Hibernate-ClassAnnotation</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<hibernate.version>5.1.7.Final</hibernate.version>
</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>${hibernate.version}</version>
</dependency>
<!-- MySQL -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.42</version>
</dependency>
</dependencies>
</project>
3.Address.java
package org.hibernate.model;
import javax.persistence.Embeddable;
@Embeddable
public class Address {
private String postcode;// 邮编
private String address;// 地址
private String telephone;// 电话
public String getPostcode() {
return postcode;
}
public void setPostcode(String postcode) {
this.postcode = postcode;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String getTelephone() {
return telephone;
}
public void setTelephone(String telephone) {
this.telephone = telephone;
}
}
4.Student.java
package org.hibernate.model;
import java.util.Date;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name="t_student")
public class Student {
private long id;// 学号
private String name;// 姓名
private Date birthday;// 出生日志
private String sex;// 性别
private Address address;// 地址
public Student() {
}
public Student(long id, String name, Date birthday, String sex, Address address) {
this.id = id;
this.name = name;
this.birthday = birthday;
this.sex = sex;
this.address = address;
}
@Id
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
}
5.hibernate.cfg.xml
<?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> <!-- SessionFactory配置 --> <session-factory> <!-- 数据库常用配置 --> <property name="connection.driver_class">com.mysql.jdbc.Driver</property> <property name="connection.username">root</property> <property name="connection.password">***</property> <property name="connection.url"> jdbc:mysql:///hibernate?useSSL=true&characterEncoding=UTF-8 </property> <property name="dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property> <!-- 开发常用配置 --> <property name="show_sql">true</property>
<property name="format_sql">true</property> <property name="hbm2ddl.auto">create</property> <!-- 引入映射类 --> <mapping class="org.hibernate.model.Student"/> </session-factory> </hibernate-configuration>
6.TestClassAnnotation.java
package org.hibernate.test;
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;
public class TestClassAnnotation {
private SessionFactory sessionFactory;
private Session session;
private Transaction transaction;
@Before
public void before() {
sessionFactory = new Configuration().configure().buildSessionFactory();// 创建SessionFactory对象
session = sessionFactory.openSession();// 获取Session对象
transaction = session.beginTransaction();// 开启事务
}
@After
public void after() {
transaction.commit();// 提交事务
session.close();// 关闭Session
sessionFactory.close();// 关闭SessionFactory
}
@Test
public void testAnnotation() {
System.out.println("执行成功...");
}
}
7.效果预览
7.1 执行testAnnotation()方法-控制台
7.2 表结构
参考：http://www.imooc.com/video/10073
Hibernate学习之类级别注解
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