給大家分享一個hibernate 自定義主鍵生成器

AssgnedTemp .java

package com.zking.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;

import com.zking.entity.Temps;

public class AssgnedTemp {
	Configuration configuration = null;
	SessionFactory sessionFactory = null;
	Session session = null;
	Transaction transaction = null;

	@Before
	public void before() {
		configuration = new Configuration().configure();
		sessionFactory = configuration.buildSessionFactory();
		// 方法的執行物件
		session = sessionFactory.openSession();
		// 提交資料一般用事務方式
		transaction = session.beginTransaction();
	}

	@After
	public void after() {
		// 提交資料
		transaction.commit();
		// 關閉資料庫的操作物件
		session.close();
		sessionFactory.close();
	}

	@Test
	public void assgneindadd() {
		// 儲存資料
		// 1. 建立物件
		Temps temps = new Temps();
		temps.setName("zhansas");
		// 2.提交資料
		session.save(temps);

	}

}
 

   1.建一個 *.hbm.xml 用來指定主鍵生成器    <generator class="com.zking.generator.MyCenerator" >

    2.建立主鍵生成器需實現  org.hibernate.id.IdentifierGenerator

    MyCenerator.java

package com.zking.generator;

import java.io.Serializable;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.engine.spi.SharedSessionContractImplementor;
import org.hibernate.id.IdentifierGenerator;
 

import com.zking.entity.Temps;

public class MyCenerator implements IdentifierGenerator {

	Temps temps = null;

	public Serializable generate(SharedSessionContractImplementor session, Object object) throws HibernateException {
		find();
		return temps.getId() + 1;
	}
 

	public void find() {
		Configuration configuration = new Configuration().configure();
		SessionFactory sessionFactory = configuration.buildSessionFactory();
		Session session = sessionFactory.openSession();
		Transaction transaction = session.beginTransaction();
		 
		temps = session.find(Temps.class, "w191");
		transaction.commit();
		// 關閉資料庫的操作物件
		session.close();
		sessionFactory.close();
	}

}
 

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- Generated 2018-9-5 19:22:39 by Hibernate Tools 3.5.0.Final -->
<hibernate-mapping>
	<class name="com.zking.entity.Temps" table="temp">
		<id name="id" type="java.lang.String">
			<column name="tid" />
		<!-- 	<generator class="guid" /> -->
			
			 <generator class="com.zking.generator.MyCenerator" >
			 
			 <param name="sequence_name">abc</param>
			 
			 </generator>
			
		</id>
		<property name="name" type="java.lang.String">
			<column name="tname" />
		</property>
	</class>
</hibernate-mapping>