Hibernate基础笔记（一）中都有哪些关键概念和操作步骤？

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Hibernate基础配置及简单的通过session操作数据

实体类：Girl

package org.tlgg.bean;

public class Girl { private Integer id; private String name; private Integer age;

public Integer getId() { return id; }}

-------------实体类 Girl------------------ package org.tlgg.bean; public class Girl { private Integer id; private String name; private Integer age; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } public Girl(Integer id, String name, Integer age) { super(); this.id = id; this.name = name; this.age = age; } public Girl() { super(); } @Override public String toString() { return "Girl [id=" + id + ", name=" + name + ", age=" + age + "]"; } } ------------实体类的配置mapper文件org.tlgg.mapper.Girl.hbm.xml-----------------------

girl_seq

-------------hibernate.cfg.xml---------------------------------

jdbc:oracle:thin:@localhost:1521:orcl

system

123456

oracle.jdbc.driver.OracleDriver

org.hibernate.dialect.Oracle10gDialect

update

true

true --------测试类--------------------- package org.tlgg.test; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; import org.tlgg.bean.Girl; public class Test { //new一个config对象，然后从配置中拿到sesssion工厂(默认从hibernate.cfg.xml中获取配置) private static SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory(); //如果配置文件命名为其他，则 new Configuration().configure("其他.xml").buildSessionFactory(); //@org.junit.Test /** * 通过session来对数据进行操作 * get(类，主键)查询 * save(对象) 添加 * update(对象) 修改 * delete(对象) 删除 * 被session所管理的对象被称为持久对象 * 在commit的时候，会自动匹配Hibernate内存中的对象字段和数据库的数据， * 多删，少加，不同就改，一切以Hibernate的持久层对象为主 * */ public void add() { Session session = sessionFactory.openSession(); //通过session拿到当前事务，然后开始操作 session.getTransaction().begin(); session.save(new Girl(101, "弱气乙女", 17)); Girl first = (Girl) session.get(Girl.class, 1); System.out.println(first); first.setName("御姐"); //提交 session.getTransaction().commit(); System.out.println(first); } public void update() { //只能修改原本存在的id的数据 Session session = sessionFactory.openSession(); session.getTransaction().begin(); Girl girl = (Girl) session.get(Girl.class, 2); System.out.println(girl); Girl badGirl = new Girl(1, "Ariana", 24); session.update(badGirl); session.getTransaction().commit(); System.out.println(session.get(Girl.class, 3)); } @org.junit.Test public void delete() { //只能修改原本存在的id的数据 Session session = sessionFactory.openSession(); session.getTransaction().begin(); Girl girl = (Girl) session.get(Girl.class, 2); session.delete(girl); session.getTransaction().commit(); System.out.println(session.get(Girl.class, 2)); } }