Hibernate基本使用
主配置
1.导包，导入约束
2.主配置文件hibernate.cfg.xml
<?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>
<!--
#hibernate.dialect org.hibernate.dialect.MySQLDialect
#hibernate.dialect org.hibernate.dialect.MySQLInnoDBDialect
#hibernate.dialect org.hibernate.dialect.MySQLMyISAMDialect
#hibernate.connection.driver_class com.mysql.jdbc.Driver
#hibernate.connection.url jdbc:mysql:///test
#hibernate.connection.username gavin
#hibernate.connection.password
-->
<!-- 数据库驱动 -->
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<!-- 数据库url -->
<property name="hibernate.connection.url">jdbc:mysql:///hibernate_32</property>
<!-- 数据库连接用户名 -->
<property name="hibernate.connection.username">root</property>
<!-- 数据库连接密码 -->
<property name="hibernate.connection.password">1234</property>
<!-- 数据库方言
不同的数据库中,sql语法略有区别. 指定方言可以让hibernate框架在生成sql语句时.针对数据库的方言生成.
sql99标准: DDL 定义语言 库表的增删改查
DCL 控制语言 事务 权限
DML 操纵语言 增删改查
注意: MYSQL在选择方言时,请选择最短的方言.
-->
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- #hibernate.show_sql true
#hibernate.format_sql true
-->
<!-- 将hibernate生成的sql语句打印到控制台 -->
<property name="hibernate.show_sql">true</property>
<!-- 将hibernate生成的sql语句格式化(语法缩进) -->
<property name="hibernate.format_sql">true</property>
<!--
## auto schema export 自动导出表结构. 自动建表
#hibernate.hbm2ddl.auto create 自动建表.每次框架运行都会创建新的表.以前表将会被覆盖,表数据会丢失.(开发环境中测试使用)
#hibernate.hbm2ddl.auto create-drop 自动建表.每次框架运行结束都会将所有表删除.(开发环境中测试使用)
#hibernate.hbm2ddl.auto update(推荐使用) 自动生成表.如果已经存在不会再生成.如果表有变动.自动更新表(不会删除任何数据).
#hibernate.hbm2ddl.auto validate 校验.不自动生成表.每次启动会校验数据库中表是否正确.校验失败.
-->
<property name="hibernate.hbm2ddl.auto">update</property>
<!-- 引入orm元数据
路径书写: 填写src下的路径
-->
<!-- 指定hibernate操作数据库时的隔离级别
#hibernate.connection.isolation 1|2|4|8
0001 1 读未提交
0010 2 读已提交
0100 4 可重复读
1000 8 串行化
-->
<property name="hibernate.connection.isolation">4</property>
<!-- 指定session与当前线程绑定 -->
<property name="hibernate.current_session_context_class">thread</property>
<mapping resource="cn/itheima/domain/Customer.hbm.xml" />
</session-factory>
</hibernate-configuration>
GenericEncodingFilter.java 乱码解决
package cn.itheima.web;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.beanutils.BeanUtils;
import cn.itheima.domain.Customer;
import cn.itheima.service.CustomerService;
import cn.itheima.service.impl.CustomerServiceImpl;
/**
* Servlet implementation class AddCustomerServlet
*/
public class AddCustomerServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private CustomerService customerService = new CustomerServiceImpl();
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1 获得参数并封装到Customer对象
Customer c = new Customer();
try {
BeanUtils.populate(c, request.getParameterMap());
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//2 调用Service保存客户
customerService .save(c);
//3 重定向到客户列表
response.sendRedirect(request.getContextPath()+"/ListCustomerServlet");
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
web.xml配置
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<display-name>hibernate_crm</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<filter>
<filter-name>encodeFilter</filter-name>
<filter-class>cn.itheima.web.filter.GenericEncodingFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>encodeFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<servlet>
<description></description>
<display-name>AddCustomerServlet</display-name>
<servlet-name>AddCustomerServlet</servlet-name>
<servlet-class>cn.itheima.web.AddCustomerServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>AddCustomerServlet</servlet-name>
<url-pattern>/AddCustomerServlet</url-pattern>
</servlet-mapping>
</web-app>
Customer.java 模型
package cn.itheima.domain;
public class Customer {
/*
* CREATE TABLE `cst_customer` (
`cust_id` BIGINT(32) NOT NULL AUTO_INCREMENT COMMENT '客户编号(主键)',
`cust_name` VARCHAR(32) NOT NULL COMMENT '客户名称(公司名称)',
`cust_source` VARCHAR(32) DEFAULT NULL COMMENT '客户信息来源',
`cust_industry` VARCHAR(32) DEFAULT NULL COMMENT '客户所属行业',
`cust_level` VARCHAR(32) DEFAULT NULL COMMENT '客户级别',
`cust_linkman` VARCHAR(64) DEFAULT NULL COMMENT '联系人',
`cust_phone` VARCHAR(64) DEFAULT NULL COMMENT '固定电话',
`cust_mobile` VARCHAR(16) DEFAULT NULL COMMENT '移动电话',
PRIMARY KEY (`cust_id`)
) ENGINE=INNODB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
*/
private Long cust_id;
private String cust_name;
private String cust_source;
private String cust_industry;
private String cust_level;
private String cust_linkman;
private String cust_phone;
private String cust_mobile;
public Long getCust_id() {
return cust_id;
}
public void setCust_id(Long cust_id) {
this.cust_id = cust_id;
}
public String getCust_name() {
return cust_name;
}
public void setCust_name(String cust_name) {
this.cust_name = cust_name;
}
public String getCust_source() {
return cust_source;
}
public void setCust_source(String cust_source) {
this.cust_source = cust_source;
}
public String getCust_industry() {
return cust_industry;
}
public void setCust_industry(String cust_industry) {
this.cust_industry = cust_industry;
}
public String getCust_level() {
return cust_level;
}
public void setCust_level(String cust_level) {
this.cust_level = cust_level;
}
public String getCust_linkman() {
return cust_linkman;
}
public void setCust_linkman(String cust_linkman) {
this.cust_linkman = cust_linkman;
}
public String getCust_phone() {
return cust_phone;
}
public void setCust_phone(String cust_phone) {
this.cust_phone = cust_phone;
}
public String getCust_mobile() {
return cust_mobile;
}
public void setCust_mobile(String cust_mobile) {
this.cust_mobile = cust_mobile;
}
@Override
public String toString() {
return "Customer [cust_id=" + cust_id + ", cust_name=" + cust_name + "]";
}
public static void main(String[] args) {
}
}
Customer.hbm.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="cn.itheima.domain" >
<class name="Customer" table="cst_customer" >
<id name="cust_id" >
<!-- generator:主键生成策略.就是每条记录录入时,主键的生成规则.(7个)
identity : 主键自增.由数据库来维护主键值.录入时不需要指定主键.
sequence: Oracle中的主键生成策略.
increment(了解): 主键自增.由hibernate来维护.每次插入前会先查询表中id最大值.+1作为新主键值.
hilo(了解): 高低位算法.主键自增.由hibernate来维护.开发时不使用.
native:hilo+sequence+identity 自动三选一策略.
uuid: 产生随机字符串作为主键. 主键类型必须为string 类型.
assigned:自然主键生成策略. hibernate不会管理主键值.由开发人员自己录入.
-->
<generator class="increment"></generator>
</id>
<property name="cust_name" column="cust_name" ></property>
<property name="cust_source" column="cust_source" ></property>
<property name="cust_industry" column="cust_industry" ></property>
<property name="cust_level" column="cust_level" ></property>
<property name="cust_linkman" column="cust_linkman" ></property>
<property name="cust_phone" column="cust_phone" ></property>
<property name="cust_mobile" column="cust_mobile" ></property>
</class>
</hibernate-mapping>
HibernateUtils统一获取Session
package cn.itheima.utils;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
public class HibernateUtils {
private static SessionFactory sf;
static{
//1 创建,调用空参构造
Configuration conf = new Configuration().configure();
//2 根据配置信息,创建 SessionFactory对象
sf = conf.buildSessionFactory();
}
//获得session => 获得全新session
public static Session openSession(){
//3 获得session
Session session = sf.openSession();
return session;
}
//获得session => 获得与线程绑定的session
public static Session getCurrentSession(){
//3 获得session
Session session = sf.getCurrentSession();
return session;
}
public static void main(String[] args) {
System.out.println(HibernateUtils.openSession());
}
}
CustomerDao接口
public interface CustomerDao {
//保存客户
void save(Customer c);
}
实现
public class CustomerDaoImpl implements CustomerDao {
public void save(Customer c) {
//1 获得session
Session session = HibernateUtils.openSession();
//2 打开事务
Transaction tx = session.beginTransaction();
//3 执行保存
session.save(c);
//4 提交事务
tx.commit();
//5 关闭资源
session.close();
}
}
AddCustomerServlet实现增加
package cn.itheima.web;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.beanutils.BeanUtils;
import cn.itheima.domain.Customer;
import cn.itheima.service.CustomerService;
import cn.itheima.service.impl.CustomerServiceImpl;
/**
* Servlet implementation class AddCustomerServlet
*/
public class AddCustomerServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private CustomerService customerService = new CustomerServiceImpl();
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1 获得参数并封装到Customer对象
Customer c = new Customer();
try {
BeanUtils.populate(c, request.getParameterMap());
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//2 调用Service保存客户
customerService .save(c);
//3 重定向到客户列表
response.sendRedirect(request.getContextPath()+"/ListCustomerServlet");
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
Hibernate三种查询
hql
package cn.itheima.e_hql;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.junit.Test;
import cn.itheima.domain.Customer;
import cn.itheima.utils.HibernateUtils;
//测试HQL语句
public class Demo {
@Test
//基本查询
public void fun1(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//1> 书写HQL语句
// String hql = " from cn.itheima.domain.Customer ";
String hql = " from Customer "; // 查询所有Customer对象
//2> 根据HQL语句创建查询对象
Query query = session.createQuery(hql);
//3> 根据查询对象获得查询结果
List<Customer> list = query.list(); // 返回list结果
//query.uniqueResult();//接收唯一的查询结果
System.out.println(list);
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
@Test
//条件查询
//HQL语句中,不可能出现任何数据库相关的信息的
public void fun2(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//1> 书写HQL语句
String hql = " from Customer where cust_id = 1 "; // 查询所有Customer对象
//2> 根据HQL语句创建查询对象
Query query = session.createQuery(hql);
//3> 根据查询对象获得查询结果
Customer c = (Customer) query.uniqueResult();
System.out.println(c);
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
@Test
//条件查询
public void fun3(){
Session session = HibernateUtils.openSession();
Transaction tx = session.beginTransaction();
//----------------------------------------------------
String hql1 = " from cn.itcast.domain.Customer where cust_id =? ";//完整写法
String hql2 = " from cn.itcast.domain.Customer where cust_id = :id ";//完整写法
Query query = session.createQuery(hql2);
// query.setParameter(0, 2l);
query.setParameter("id", 2l);
List list = query.list();
System.out.println(list);
//----------------------------------------------------
tx.commit();
session.close();
}
@Test
//统计查询
//count 计数
//sum 求和
//avg 平均数
//max
//min
public void fun5(){
Session session = HibernateUtils.openSession();
Transaction tx = session.beginTransaction();
//----------------------------------------------------
String hql1 = " select count(*) from cn.itcast.domain.Customer ";//完整写法
String hql2 = " select sum(cust_id) from cn.itcast.domain.Customer ";//完整写法
String hql3 = " select avg(cust_id) from cn.itcast.domain.Customer ";//完整写法
String hql4 = " select max(cust_id) from cn.itcast.domain.Customer ";//完整写法
String hql5 = " select min(cust_id) from cn.itcast.domain.Customer ";//完整写法
Query query = session.createQuery(hql5);
Number number = (Number) query.uniqueResult();
System.out.println(number);
//----------------------------------------------------
tx.commit();
session.close();
}
@Test
//分页查询
public void fun6(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//1> 书写HQL语句
String hql = " from Customer "; // 查询所有Customer对象
//2> 根据HQL语句创建查询对象
Query query = session.createQuery(hql);
//设置分页信息 limit ?,?
query.setFirstResult(1);
query.setMaxResults(1);
//3> 根据查询对象获得查询结果
List<Customer> list = query.list();
System.out.println(list);
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
}
//回顾-原生SQL
// 交叉连接-笛卡尔积(避免)
// select * from A,B
// 内连接
// |-隐式内连接
// select * from A,B where b.aid = a.id
// |-显式内连接
// select * from A inner join B on b.aid = a.id
// 外连接
// |- 左外
// select * from A left [outer] join B on b.aid = a.id
// |- 右外
// select * from A right [outer] join B on b.aid = a.id
//HQL 内连接 => 将连接的两端对象分别返回.放到数组中.
public void fun1(){
Session session = HibernateUtils.openSession();
Transaction tx = session.beginTransaction();
//----------------------------------------------------
String hql = " from Customer c inner join c.linkMens ";
Query query = session.createQuery(hql);
List<Object[]> list = query.list();
for(Object[] arr : list){
System.out.println(Arrays.toString(arr));
}
//----------------------------------------------------
tx.commit();
session.close();
}
@Test
//HQL 迫切内连接 => 帮我们进行封装.返回值就是一个对象
public void fun2(){
Session session = HibernateUtils.openSession();
Transaction tx = session.beginTransaction();
//----------------------------------------------------
String hql = " from Customer c inner join fetch c.linkMens ";
Query query = session.createQuery(hql);
List<Customer> list = query.list();
System.out.println(list);
//----------------------------------------------------
tx.commit();
session.close();
}
@Test
//HQL 左外连接 => 将连接的两端对象分别返回.放到数组中.
public void fun3(){
Session session = HibernateUtils.openSession();
Transaction tx = session.beginTransaction();
//----------------------------------------------------
String hql = " from Customer c left join c.linkMens ";
Query query = session.createQuery(hql);
List<Object[]> list = query.list();
for(Object[] arr : list){
System.out.println(Arrays.toString(arr));
}
//----------------------------------------------------
tx.commit();
session.close();
}
@Test
//HQL 右外连接 => 将连接的两端对象分别返回.放到数组中.
public void fun4(){
Session session = HibernateUtils.openSession();
Transaction tx = session.beginTransaction();
//----------------------------------------------------
String hql = " from Customer c right join c.linkMens ";
Query query = session.createQuery(hql);
List<Object[]> list = query.list();
for(Object[] arr : list){
System.out.println(Arrays.toString(arr));
}
//----------------------------------------------------
tx.commit();
session.close();
}
Criteria
package cn.itheima.f_criteria;
import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.Projections;
import org.hibernate.criterion.Restrictions;
import org.junit.Test;
import cn.itheima.domain.Customer;
import cn.itheima.utils.HibernateUtils;
//测试Criteria查询
public class Demo {
@Test
//基本查询
public void fun1(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//查询所有的Customer对象
Criteria criteria = session.createCriteria(Customer.class);
List<Customer> list = criteria.list();
System.out.println(list);
// Customer c = (Customer) criteria.uniqueResult();
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
@Test
//条件查询
//HQL语句中,不可能出现任何数据库相关的信息的
// > gt
// >= ge
// < lt
// <= le
// == eq
// != ne
// in in
// between and between
// like like
// is not null isNotNull
// is null isNull
// or or
// and and
public void fun2(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//创建criteria查询对象
Criteria criteria = session.createCriteria(Customer.class);
//添加查询参数 => 查询cust_id为1的Customer对象
criteria.add(Restrictions.eq("cust_id", 1l));
//执行查询获得结果
Customer c = (Customer) criteria.uniqueResult();
System.out.println(c);
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
@Test
//分页查询
public void fun3(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//创建criteria查询对象
Criteria criteria = session.createCriteria(Customer.class);
//设置分页信息 limit ?,?
criteria.setFirstResult(1);
criteria.setMaxResults(2);
//执行查询
List<Customer> list = criteria.list();
System.out.println(list);
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
@Test
//查询总记录数
public void fun4(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//创建criteria查询对象
Criteria criteria = session.createCriteria(Customer.class);
//设置查询的聚合函数 => 总行数
criteria.setProjection(Projections.rowCount());
//执行查询
Long count = (Long) criteria.uniqueResult();
System.out.println(count);
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
@Test
// 离线
public void fun1(){
//Service/web层
DetachedCriteria dc = DetachedCriteria.forClass(Customer.class);
dc.add(Restrictions.idEq(6l));//拼装条件(全部与普通Criteria一致)
//----------------------------------------------------
Session session = HibernateUtils.openSession();
Transaction tx = session.beginTransaction();
//----------------------------------------------------
Criteria c = dc.getExecutableCriteria(session);
List list = c.list();
System.out.println(list);
//----------------------------------------------------
tx.commit();
session.close();
}
}
SQL
package cn.itheima.g_sql;
import java.util.Arrays;
import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.Projections;
import org.hibernate.criterion.Restrictions;
import org.junit.Test;
import cn.itheima.domain.Customer;
import cn.itheima.utils.HibernateUtils;
//测试原生SQL查询
public class Demo {
@Test
//基本查询
public void fun1(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//1 书写sql语句
String sql = "select * from cst_customer";
//2 创建sql查询对象
SQLQuery query = session.createSQLQuery(sql);
//3 调用方法查询结果
List<Object[]> list = query.list();
//query.uniqueResult();
for(Object[] objs : list){
System.out.println(Arrays.toString(objs));
}
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
@Test
//基本查询
public void fun2(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//1 书写sql语句
String sql = "select * from cst_customer";
//2 创建sql查询对象
SQLQuery query = session.createSQLQuery(sql);
//指定将结果集封装到哪个对象中
query.addEntity(Customer.class);
//3 调用方法查询结果
List<Customer> list = query.list();
System.out.println(list);
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
@Test
//条件查询
public void fun3(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//1 书写sql语句
String sql = "select * from cst_customer where cust_id = ? ";
//2 创建sql查询对象
SQLQuery query = session.createSQLQuery(sql);
query.setParameter(0, 1l);
//指定将结果集封装到哪个对象中
query.addEntity(Customer.class);
//3 调用方法查询结果
List<Customer> list = query.list();
System.out.println(list);
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
@Test
//分页查询
public void fun4(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 控制事务
Transaction tx = session.beginTransaction();
//3执行操作
//-------------------------------------------
//1 书写sql语句
String sql = "select * from cst_customer limit ?,? ";
//2 创建sql查询对象
SQLQuery query = session.createSQLQuery(sql);
query.setParameter(0, 0);
query.setParameter(1, 1);
//指定将结果集封装到哪个对象中
query.addEntity(Customer.class);
//3 调用方法查询结果
List<Customer> list = query.list();
System.out.println(list);
//-------------------------------------------
//4提交事务.关闭资源
tx.commit();
session.close();// 游离|托管 状态, 有id , 没有关联
}
}
加载策略
@Test
// load方法(默认):是在执行时,不发送任何sql语句.返回一个对象.使用该对象时,才执行查询.
// 延迟加载: 仅仅获得没有使用.不会查询.在使用时才进行查询.
// 是否对类进行延迟加载: 可以通过在class元素上配置lazy属性来控制.
//lazy:true 加载时,不查询.使用时才查询b
//lazy:false 加载时立即查询.
public void fun2(){
Session session = HibernateUtils.openSession();
Transaction tx = session.beginTransaction();
//----------------------------------------------------
Customer c = session.load(Customer.class, 2l);
//----------------------------------------------------
tx.commit();
session.close();
System.out.println(c);
}
多对一
Customer.java
public class Customer {
/*
* CREATE TABLE `cst_customer` (
`cust_id` BIGINT(32) NOT NULL AUTO_INCREMENT COMMENT '客户编号(主键)',
`cust_name` VARCHAR(32) NOT NULL COMMENT '客户名称(公司名称)',
`cust_source` VARCHAR(32) DEFAULT NULL COMMENT '客户信息来源',
`cust_industry` VARCHAR(32) DEFAULT NULL COMMENT '客户所属行业',
`cust_level` VARCHAR(32) DEFAULT NULL COMMENT '客户级别',
`cust_linkman` VARCHAR(64) DEFAULT NULL COMMENT '联系人',
`cust_phone` VARCHAR(64) DEFAULT NULL COMMENT '固定电话',
`cust_mobile` VARCHAR(16) DEFAULT NULL COMMENT '移动电话',
PRIMARY KEY (`cust_id`)
) ENGINE=INNODB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
*/
private Long cust_id;
private String cust_name;
private String cust_source;
private String cust_industry;
private String cust_level;
private String cust_linkman;
private String cust_phone;
private String cust_mobile;
//使用set集合,表达一对多关系
private Set<LinkMan> linkMens = new HashSet<LinkMan>();
public Set<LinkMan> getLinkMens() {
return linkMens;
}
public void setLinkMens(Set<LinkMan> linkMens) {
this.linkMens = linkMens;
}
public Long getCust_id() {
return cust_id;
}
public void setCust_id(Long cust_id) {
this.cust_id = cust_id;
}
public String getCust_name() {
return cust_name;
}
public void setCust_name(String cust_name) {
this.cust_name = cust_name;
}
public String getCust_source() {
return cust_source;
}
public void setCust_source(String cust_source) {
this.cust_source = cust_source;
}
public String getCust_industry() {
return cust_industry;
}
public void setCust_industry(String cust_industry) {
this.cust_industry = cust_industry;
}
public String getCust_level() {
return cust_level;
}
public void setCust_level(String cust_level) {
this.cust_level = cust_level;
}
public String getCust_linkman() {
return cust_linkman;
}
public void setCust_linkman(String cust_linkman) {
this.cust_linkman = cust_linkman;
}
public String getCust_phone() {
return cust_phone;
}
public void setCust_phone(String cust_phone) {
this.cust_phone = cust_phone;
}
public String getCust_mobile() {
return cust_mobile;
}
public void setCust_mobile(String cust_mobile) {
this.cust_mobile = cust_mobile;
}
@Override
public String toString() {
return "Customer [cust_id=" + cust_id + ", cust_name=" + cust_name + "]";
}
}
LinkMan.java
//联系人实体
public class LinkMan {
/*
* CREATE TABLE `cst_linkman` (
`lkm_id` bigint(32) NOT NULL AUTO_INCREMENT COMMENT '联系人编号(主键)',
`lkm_name` varchar(16) DEFAULT NULL COMMENT '联系人姓名',
`lkm_cust_id` bigint(32) NOT NULL COMMENT '客户id',
`lkm_gender` char(1) DEFAULT NULL COMMENT '联系人性别',
`lkm_phone` varchar(16) DEFAULT NULL COMMENT '联系人办公电话',
`lkm_mobile` varchar(16) DEFAULT NULL COMMENT '联系人手机',
`lkm_email` varchar(64) DEFAULT NULL COMMENT '联系人邮箱',
`lkm_qq` varchar(16) DEFAULT NULL COMMENT '联系人qq',
`lkm_position` varchar(16) DEFAULT NULL COMMENT '联系人职位',
`lkm_memo` varchar(512) DEFAULT NULL COMMENT '联系人备注',
PRIMARY KEY (`lkm_id`),
KEY `FK_cst_linkman_lkm_cust_id` (`lkm_cust_id`),
CONSTRAINT `FK_cst_linkman_lkm_cust_id` FOREIGN KEY (`lkm_cust_id`) REFERENCES `cst_customer` (`cust_id`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8;
*/
private Long lkm_id;
private Character lkm_gender;
private String lkm_name;
private String lkm_phone;
private String lkm_email;
private String lkm_qq;
private String lkm_mobile;
private String lkm_memo;
private String lkm_position;
//表达多对一关系
private Customer customer ;
public Customer getCustomer() {
return customer;
}
public void setCustomer(Customer customer) {
this.customer = customer;
}
public Long getLkm_id() {
return lkm_id;
}
public void setLkm_id(Long lkm_id) {
this.lkm_id = lkm_id;
}
public Character getLkm_gender() {
return lkm_gender;
}
public void setLkm_gender(Character lkm_gender) {
this.lkm_gender = lkm_gender;
}
public String getLkm_name() {
return lkm_name;
}
public void setLkm_name(String lkm_name) {
this.lkm_name = lkm_name;
}
public String getLkm_phone() {
return lkm_phone;
}
public void setLkm_phone(String lkm_phone) {
this.lkm_phone = lkm_phone;
}
public String getLkm_email() {
return lkm_email;
}
public void setLkm_email(String lkm_email) {
this.lkm_email = lkm_email;
}
public String getLkm_qq() {
return lkm_qq;
}
public void setLkm_qq(String lkm_qq) {
this.lkm_qq = lkm_qq;
}
public String getLkm_mobile() {
return lkm_mobile;
}
public void setLkm_mobile(String lkm_mobile) {
this.lkm_mobile = lkm_mobile;
}
public String getLkm_memo() {
return lkm_memo;
}
public void setLkm_memo(String lkm_memo) {
this.lkm_memo = lkm_memo;
}
public String getLkm_position() {
return lkm_position;
}
public void setLkm_position(String lkm_position) {
this.lkm_position = lkm_position;
}
}
Customer.hbm.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="cn.itcast.domain" >
<class name="Customer" table="cst_customer" >
<id name="cust_id" >
<generator class="native"></generator>
</id>
<property name="cust_name" column="cust_name" ></property>
<property name="cust_source" column="cust_source" ></property>
<property name="cust_industry" column="cust_industry" ></property>
<property name="cust_level" column="cust_level" ></property>
<property name="cust_linkman" column="cust_linkman" ></property>
<property name="cust_phone" column="cust_phone" ></property>
<property name="cust_mobile" column="cust_mobile" ></property>
<!-- 集合,一对多关系,在配置文件中配置 -->
<!--
name属性:集合属性名
column属性: 外键列名
class属性: 与我关联的对象完整类名
-->
<!--
级联操作: cascade
save-update: 级联保存更新
delete:级联删除
all:save-update+delete
级联操作: 简化操作.目的就是为了少些两行代码.
-->
<!-- inverse属性: 配置关系是否维护.
true: customer不维护关系
false(默认值): customer维护关系
inverse属性: 性能优化.提高关系维护的性能.
原则: 无论怎么放弃,总有一方必须要维护关系.
一对多关系中: 一的一方放弃.也只能一的一方放弃.多的一方不能放弃.
-->
<set name="linkMens" inverse="true" cascade="delete" >
<key column="lkm_cust_id" ></key>
<one-to-many class="LinkMan" />
</set>
</class>
</hibernate-mapping>
LinkMan.hbm.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="cn.itcast.domain" >
<class name="LinkMan" table="cst_linkman" >
<id name="lkm_id" >
<generator class="native"></generator>
</id>
<property name="lkm_gender" ></property>
<property name="lkm_name" ></property>
<property name="lkm_phone" ></property>
<property name="lkm_email" ></property>
<property name="lkm_qq" ></property>
<property name="lkm_mobile" ></property>
<property name="lkm_memo" ></property>
<property name="lkm_position" ></property>
<!-- 多对一 -->
<!--
name属性:引用属性名
column属性: 外键列名
class属性: 与我关联的对象完整类名
-->
<!--
级联操作: cascade
save-update: 级联保存更新
delete:级联删除
all:save-update+delete
级联操作: 简化操作.目的就是为了少些两行代码.
-->
<!-- 多的一方: 不能放弃维护关系的.外键字段就在多的一方. -->
<many-to-one name="customer" column="lkm_cust_id" class="Customer" >
</many-to-one>
</class>
</hibernate-mapping>
Demo
//测试级联操作
public class Demo2 {
@Test
//保存客户 以及客户 下的联系人
//cascade:save-update
public void fun1(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 开启事务
Transaction tx = session.beginTransaction();
//-------------------------------------------------
//3操作
Customer c = new Customer();
c.setCust_name("客户");
LinkMan lm1 = new LinkMan();
lm1.setLkm_name("联系人1");
LinkMan lm2 = new LinkMan();
lm2.setLkm_name("联系人2");
//表达一对多,客户下有多个联系人
c.getLinkMens().add(lm1);
c.getLinkMens().add(lm2);
//表达对对对,联系人属于哪个客户
lm1.setCustomer(c);
lm2.setCustomer(c);
session.save(c);
// session.save(lm1);
// session.save(lm2);
//-------------------------------------------------
//4提交事务
tx.commit();
//5关闭资源
session.close();
}
@Test
//测试删除客户时,级联删除客户下的联系人
//cascade:delete
public void fun2(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 开启事务
Transaction tx = session.beginTransaction();
//-------------------------------------------------
//3操作
//1> 获得要操作的客户对象
Customer c = session.get(Customer.class,1l);
//2>调用delete删除客户
session.delete(c);
//-------------------------------------------------
//4提交事务
tx.commit();
//5关闭资源
session.close();
}
@Test
//保存联系人以及联系人对应的客户
//cascade:save-update
public void fun3(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 开启事务
Transaction tx = session.beginTransaction();
//-------------------------------------------------
//3操作
Customer c = new Customer();
c.setCust_name("客户");
LinkMan lm1 = new LinkMan();
lm1.setLkm_name("刘总");
//表达一对多,客户下有多个联系人
c.getLinkMens().add(lm1);
//表达对对对,联系人属于哪个客户
lm1.setCustomer(c);
session.save(lm1);
//4提交事务
tx.commit();
//5关闭资源
session.close();
}
@Test
//删除客户
public void fun2(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 开启事务
Transaction tx = session.beginTransaction();
//-------------------------------------------------
//3操作
Customer customer = session.get(Customer.class, 1l);
session.delete(customer);
//-------------------------------------------------
//4提交事务
tx.commit();
//5关闭资源
session.close();
}
public void fun1(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 开启事务
Transaction tx = session.beginTransaction();
//-------------------------------------------------
//3操作
Customer c = new Customer();
c.setCust_name("传智播客");
LinkMan lm1 = new LinkMan();
lm1.setLkm_name("黎活明");
LinkMan lm2 = new LinkMan();
lm2.setLkm_name("刘悦东");
//表达一对多,客户下有多个联系人.
// 如果客户放弃维护与联系人的关系. 维护关系的代码可以省略
//c.getLinkMens().add(lm1);
//c.getLinkMens().add(lm2);
//表达对对对,联系人属于哪个客户
lm1.setCustomer(c);
lm2.setCustomer(c);
session.save(c);
session.save(lm1);
session.save(lm2);
//-------------------------------------------------
//4提交事务
tx.commit();
//5关闭资源
session.close();
}
}
多对多
角色表的配置
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="cn.itcast.domain" >
<class name="Role" table="sys_role" >
<id name="role_id" >
<generator class="native"></generator>
</id>
<property name="role_name" ></property>
<property name="role_memo" ></property>
<!-- 使用inverse属性
true: 放弃维护外键关系
false(默认值):维护关系
结论: 将来在开发中,如果遇到多对多关系.一定要选择一方放弃维护关系.
一般谁来放弃要看业务方向. 例如录入员工时,需要为员工指定所属角色.
那么业务方向就是由员工维护角色. 角色不需要维护与员工关系.角色放弃维护
-->
<set name="users" table="sys_user_role" inverse="true" >
<key column="role_id" ></key>
<many-to-many class="User" column="user_id" ></many-to-many>
</set>
</class>
</hibernate-mapping>
用户表的配置
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="cn.itcast.domain" >
<class name="User" table="sys_user" >
<id name="user_id" >
<generator class="native"></generator>
</id>
<property name="user_code" ></property>
<property name="user_name" ></property>
<property name="user_password" ></property>
<property name="user_state" ></property>
<!-- 多对多关系表达 -->
<!--
name: 集合属性名
table: 配置中间表名
key
|-column:外键,别人引用"我"的外键列名
class: 我与哪个类是多对多关系
column:外键.我引用比人的外键列名
-->
<!-- cascade级联操作:
save-update: 级联保存更新
delete:级联删除
all:级联保存更新+级联删除
结论: cascade简化代码书写.该属性使不使用无所谓. 建议要用只用save-update.
如果使用delete操作太过危险.尤其在多对多中.不建议使用.
-->
<set name="roles" table="sys_user_role" cascade="save-update" >
<key column="user_id" ></key>
<many-to-many class="Role" column="role_id" ></many-to-many>
</set>
</class>
</hibernate-mapping>
操作
package cn.itcast.b_many2many;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.junit.Test;
import cn.itcast.domain.Role;
import cn.itcast.domain.User;
import cn.itcast.utils.HibernateUtils;
//多对多关系操作
public class Demo {
@Test
//保存员工以及角色
public void fun1(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 开启事务
Transaction tx = session.beginTransaction();
//-------------------------------------------------
//3操作
//1> 创建两个 User
User u1 = new User();
u1.setUser_name("小子");
User u2 = new User();
u2.setUser_name("金家");
//2> 创建两个 Role
Role r1 = new Role();
r1.setRole_name("保洁");
Role r2 = new Role();
r2.setRole_name("保安");
//3> 用户表达关系
u1.getRoles().add(r1);
u1.getRoles().add(r2);
u2.getRoles().add(r1);
u2.getRoles().add(r2);
//4> 角色表达关系
r1.getUsers().add(u1);
r1.getUsers().add(u2);
r2.getUsers().add(u1);
r2.getUsers().add(u2);
//5> 调用Save方法一次保存
session.save(u1);
session.save(u2);
session.save(r1);
session.save(r2);
//-------------------------------------------------
//4提交事务
tx.commit();
//5关闭资源
session.close();
}
@Test
//为郝强勇新增一个角色
public void fun3(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 开启事务
Transaction tx = session.beginTransaction();
//-------------------------------------------------
//3操作
//1> 获得郝强勇用户
User user = session.get(User.class, 1l);
//2> 创建公关角色
Role r = new Role();
r.setRole_name("男公关");
//3> 将角色添加到用户中
user.getRoles().add(r);
//4> 将角色转换为持久化
//session.save(r);
//-------------------------------------------------
//4提交事务
tx.commit();
//5关闭资源
session.close();
}
@Test
//为郝强勇解除一个角色
public void fun4(){
//1 获得session
Session session = HibernateUtils.openSession();
//2 开启事务
Transaction tx = session.beginTransaction();
//-------------------------------------------------
//3操作
//1> 获得郝强勇用户
User user = session.get(User.class, 1l);
//2> 获得要操作的角色对象(保洁,保安)
Role r1 = session.get(Role.class, 1l);
Role r2 = session.get(Role.class, 2l);
//3> 将角色从用户的角色集合中移除
user.getRoles().remove(r1);
user.getRoles().remove(r2);
//-------------------------------------------------
//4提交事务
tx.commit();
//5关闭资源
session.close();
}
}
model
public class Role {
private Long role_id;
private String role_name;
private String role_memo;
//表达多对多
private Set<User> users = new HashSet<User>();
public Long getRole_id() {
return role_id;
}
public void setRole_id(Long role_id) {
this.role_id = role_id;
}
public String getRole_name() {
return role_name;
}
public void setRole_name(String role_name) {
this.role_name = role_name;
}
public String getRole_memo() {
return role_memo;
}
public void setRole_memo(String role_memo) {
this.role_memo = role_memo;
}
public Set<User> getUsers() {
return users;
}
public void setUsers(Set<User> users) {
this.users = users;
}
}
public class User {
private Long user_id;
private String user_code;
private String user_name;
private String user_password;
private Character user_state;
//表达多对多
private Set<Role> roles = new HashSet<Role>();
public Long getUser_id() {
return user_id;
}
public void setUser_id(Long user_id) {
this.user_id = user_id;
}
public String getUser_code() {
return user_code;
}
public void setUser_code(String user_code) {
this.user_code = user_code;
}
public String getUser_name() {
return user_name;
}
public void setUser_name(String user_name) {
this.user_name = user_name;
}
public String getUser_password() {
return user_password;
}
public void setUser_password(String user_password) {
this.user_password = user_password;
}
public Character getUser_state() {
return user_state;
}
public void setUser_state(Character user_state) {
this.user_state = user_state;
}
public Set<Role> getRoles() {
return roles;
}
public void setRoles(Set<Role> roles) {
this.roles = roles;
}
}
