今天说点基础的东西,说说如何通过SchemaExport跟hibernate的配置文件生成表结构。其实方法非常简单,只需要两个配置文件,两个Java类就可以完成。
首先要生成表,得先有实体类,以Person.java为例:
- /**
- *
- * @author Administrator
- * @hibernate.class table="T_Person"
- */
- public class Person {
- /**
- * @hibernate.id
- * generator-class="native"
- */
- private int id;
- /**
- * @hibernate.property
- */
- private String name;
- /**
- * @hibernate.property
- */
- private String sex;
- /**
- * @hibernate.property
- */
- private String address;
- /**
- * @hibernate.property
- */
- private String duty;
- /**
- * @hibernate.property
- */
- private String phone;
- /**
- * @hibernate.property
- */
- private String description;
- /**
- * @hibernate.many-to-one
- */
- private Orgnization org;
- public String getAddress() {
- return address;
- }
- public void setAddress(String address) {
- this.address = address;
- }
- public String getDescription() {
- return description;
- }
- public void setDescription(String description) {
- this.description = description;
- }
- public String getDuty() {
- return duty;
- }
- public void setDuty(String duty) {
- this.duty = duty;
- }
- 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 String getPhone() {
- return phone;
- }
- public void setPhone(String phone) {
- this.phone = phone;
- }
- public String getSex() {
- return sex;
- }
- public void setSex(String sex) {
- this.sex = sex;
- }
- public Orgnization getOrg() {
- return org;
- }
- public void setOrg(Orgnization org) {
- this.org = org;
- }
- }
接下来就是Person类对应的配置文件Person.hbm.xml,配置如下:
- <hibernate-mapping>
- <class table="T_Person" name="com.tgb.model.Person">
- <id name="id">
- <generator class="native"/>
- </id>
- <property name="name"/>
- <property name="sex"/>
- <property name="address"/>
- <property name="duty"/>
- <property name="phone"/>
- <property name="description"/>
- <many-to-one name="org"></many-to-one>
- </class>
- </hibernate-mapping>
还有包含Person.hbm.xml相关信息的Hibernate默认配置文件,hibernate.cfg.xml:
- <hibernate-configuration>
- <session-factory>
- <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
- <property name="hibernate.connection.url">jdbc:mysql://127.0.0.1/test</property>
- <property name="hibernate.connection.username">root</property>
- <property name="hibernate.connection.password">123456</property>
- <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
- <property name="hibernate.show_sql">true</property>
- <property name="hibernate.hbm2ddl.auto">update</property>
- <property name="hibernate.current_session_context_class">thread</property>
- <mapping resource="com/tgb/model/Person.hbm.xml"/>
- </session-factory>
- </hibernate-configuration>
万事俱备只欠东风,最后我们还需要一个根据上述内容生成数据表的小工具,即ExportDB.Java:
- import org.hibernate.cfg.Configuration;
- import org.hibernate.tool.hbm2ddl.SchemaExport;
- public class ExportDB {
- /**
- * @param args
- */
- public static void main(String[] args) {
- // 默认读取hibernate.cfg.xml文件
- Configuration cfg = new Configuration().configure();
- // 生成并输出sql到文件(当前目录)和数据库
- SchemaExport export = new SchemaExport(cfg);
- // 创建表结构,第一个true 表示在控制台打印sql语句,第二个true 表示导入sql语句到数据库
- export.create(true, true);
- }
- }
完成以上步骤以后,只需要执行ExportDB类即可,当然前提是已经在MySQL中创建了对应的数据库,我们这里创建了一个名为test的测试数据库。执行成功之后我们就可以看到数据库里已经有了我们的t_person表了,如下图所示: