在工作中遇到数据库表名会根据月份变化的情况,比如3月生成的表叫detail_201803,4月生成的表叫detail_201804,以此类推。每个表结构相同。就希望通过使用hibernate中的NameStrategy来实现动态表名。
主要参考文章:https://blog.youkuaiyun.com/lmy86263/article/details/52640764
https://blog.youkuaiyun.com/meng2602956882/article/details/22914493
其中,我的hibernate配置是写在xml文件中而不是注释中的,跟网上已有的都不同,所以在这里记录一下。
1. 第一步先编写一个自己的NameStrategy,代码如下:
package edu.sjtu.utils;
import org.hibernate.cfg.DefaultNamingStrategy;
import org.hibernate.cfg.ImprovedNamingStrategy;
import org.hibernate.util.StringHelper;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
public class MyNameStrategy extends ImprovedNamingStrategy {
@Override
public String classToTableName(String className) {
String tableName;
DateFormat format = new SimpleDateFormat("yyyyMM");
String currentDate = format.format(new Date());
if("edu.sjtu.entity.Detail".equals(className)){
tableName = "detail_" + currentDate;
// tableName = "detail_" + "201803";
}else{
tableName = className;
}
return addUnderscores(StringHelper.unqualify(tableName));
}
}
2.然后修改applicationContext.xml配置中的namingStrategy
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean" >
<property name="dataSource" ref="dataSource1"/>
<!-- 只改namingStrategy中的值,别的不用管 -->
<property name="namingStrategy">
<bean class="edu.sjtu.utils.MyNameStrategy"></bean>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
<prop key="hibernate.dialect">${hibernate.dialect}</prop>
<prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
</props>
</property>
<!-- 自动扫描注解方式配置的hibernate类文件 -->
<property name="mappingLocations" value="classpath:mapper/*.hbm.xml"></property>
</bean>
3.修改hibernate实体与数据表对应文件detail.hbm.xml ,把原来
<class name="Detail" table="detail">改成<class name="Detail">,其他不用改。
<?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 package="edu.sjtu.entity">
<class name="Detail">
<id name="jaccount" column="JACCOUNT" length="100">
<generator class="assigned"/>
</id>
<property name="creator" length="50">
<column name="CREATOR"></column>
</property>
</class>
</hibernate-mapping
4.重启tomcat ,ok