接着上一节，工程结构：
jar包没有变化；
一、HibernateUtil 封装：
com.cy.util.HibernateUtil.java:
package com.cy.util; import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration; public class HibernateUtil { private static final SessionFactory sessionFactory = buildSessionFactory(); private static SessionFactory buildSessionFactory(){
Configuration configuration = new Configuration().configure(); //实例化配置文件,默认指定的就是hibernate.cfg.xml
StandardServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();//实例化服务登记,服务注册
return configuration.buildSessionFactory(serviceRegistry); //获取session工厂
} //获取sessionFactory，是单例的
public static SessionFactory getSessionFactory(){
return sessionFactory;
}
}
二、XML 版CRUD 实现：
对Student类进行xml配置，crud操作；
com.cy.model.student.java:
package com.cy.model;
public class Student {
private long id;
private String name;
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;
}
@Override
public String toString() {
return "Student [id=" + id + ", name=" + name + "]";
}
}
Student.hbm.xml:
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="com.cy.model">
<class name="Student" table="t_student">
<!--
<id>代表主键
类的属性名是id，对应表中列名是stuId
-->
<id name="id" column="stuId">
<!-- 主键生成策略，这里采用mysql的native，自增 -->
<generator class="native"></generator>
</id> <!-- 普通属性采用property
不写column，那么数据库table的列名也叫name
-->
<property name="name"></property> </class> </hibernate-mapping>
com.cy.service.StudentTest.java:--这里是测试类，对Student进行CRUD：
package com.cy.service; import java.util.List; import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory; import com.cy.model.Student;
import com.cy.util.HibernateUtil; public class StudentTest { private static SessionFactory sessionFactory = HibernateUtil.getSessionFactory(); //添加学生
private void add(){
Session session = sessionFactory.openSession(); //生成一个session
session.beginTransaction(); //开启事务 Student s = new Student();
s.setName("张三");
session.save(s); session.getTransaction().commit(); //提交事务
session.close(); //关闭session
} //删除学生
private void delete(){
Session session = sessionFactory.openSession();
session.beginTransaction(); Student student = (Student) session.get(Student.class, 1L);
session.delete(student); session.getTransaction().commit();
session.close();
} //更新学生
private void update(){
Session session = sessionFactory.openSession();
session.beginTransaction(); Student student = (Student) session.get(Student.class, 6L);
student.setName("张三22");
session.save(student); session.getTransaction().commit();
session.close();
} //查找所有学生
private void getAllStudents(){
Session session = sessionFactory.openSession();
session.beginTransaction(); String hql = "from Student";
Query query = session.createQuery(hql);
List<Student> studentList = query.list();
for(Student student : studentList){
System.out.println(student);
} session.getTransaction().commit();
session.close();
} public static void main(String[] args) {
StudentTest studentTest = new StudentTest();
// studentTest.add();
// studentTest.delete();
// studentTest.update();
studentTest.getAllStudents();
}
}
hibernate.cfg.xml中加入Student映射（为了方便后面，也加入了Teacher）：
<?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> <!--数据库连接设置 -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property>
<property name="connection.username">root</property>
<property name="connection.password">root</property> <!-- 方言 -->
<property name="dialect">org.hibernate.dialect.MySQL5Dialect</property> <!-- 控制台显示SQL -->
<property name="show_sql">true</property> <!-- 自动更新表结构 -->
<property name="hbm2ddl.auto">update</property> <mapping resource="com/cy/model/Student.hbm.xml"/>
<mapping class="com.cy.model.Teacher"/>
</session-factory> </hibernate-configuration>
StudentTest.java运行main函数，结果：
删除：
修改：
查询所有：
三、注解版CRUD 实现
1.注解版CRUD：注解版的很方便，官方也推荐使用；
2.运行测试程序，hibernate会根据映射关系，如有没有表的话，自动创建表。（如果配置了hbm2ddl.auto为update）；
这里是对Teacher类进行注解的配置，然后进行CRUD操作:
com.cy.model.Teacher.java:
package com.cy.model; import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table; import org.hibernate.annotations.GenericGenerator; //@Entity代表Teacher是一个映射实体
@Entity
@Table(name="t_teacher")
public class Teacher {
private long id;
private String name; //@Id代表id是一个主键
//@GenericGenerator配置主键生成策略 name是起个名字，strategy是具体的策略;
//@GeneratedValue配置生成策略为@GenericGenerator的名字
@Id
@GeneratedValue(generator="_native")
@GenericGenerator(name="_native",strategy="native")
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;
} @Override
public String toString() {
return "Teacher [id=" + id + ", name=" + name + "]";
} }
将Teacher类加入hibernate.cfg.xml：
<mapping class="com.cy.model.Teacher"/>
com.cy.service.TeacherTest.java测试代码：
package com.cy.service; import java.util.List; import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory; import com.cy.model.Teacher;
import com.cy.util.HibernateUtil; public class TeacherTest { private static SessionFactory sessionFactory = HibernateUtil.getSessionFactory(); //添加老师
private void add(){
Session session = sessionFactory.openSession(); //生成一个session
session.beginTransaction(); //开启事务 Teacher s = new Teacher();
s.setName("张三");
session.save(s); session.getTransaction().commit(); //提交事务
session.close(); //关闭session
} //删除老师
private void delete(){
Session session = sessionFactory.openSession();
session.beginTransaction(); Teacher Teacher = (Teacher) session.get(Teacher.class, 1L);
session.delete(Teacher); session.getTransaction().commit();
session.close();
} //更新老师
private void update(){
Session session = sessionFactory.openSession();
session.beginTransaction(); Teacher Teacher = (Teacher) session.get(Teacher.class, 4L);
Teacher.setName("张老师22");
session.save(Teacher); session.getTransaction().commit();
session.close();
} //查找所有老师
private void getAllTeachers(){
Session session = sessionFactory.openSession();
session.beginTransaction(); String hql = "from Teacher";
Query query = session.createQuery(hql);
List<Teacher> TeacherList = query.list();
for(Teacher Teacher : TeacherList){
System.out.println(Teacher);
} session.getTransaction().commit();
session.close();
} public static void main(String[] args) {
TeacherTest TeacherTest = new TeacherTest();
// TeacherTest.add();
// TeacherTest.delete();
// TeacherTest.update();
TeacherTest.getAllTeachers();
}
}
测试结果和StudentTest结果差不多，不再说明了。打印出来的语句也基本一样的。