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1、 属性的映射文件
<!—name是实体类的全路径 ，table重命名 <class name="com.creasoft.entity.Products" table="product"> <id name="pid" column="p_id" type="long"> <generator class="increment"></generator> </id> <!—unique 定义的是否重复 <property name="productName" column="product_name" type="string" not-null="true" unique="true" length="20"> </property> <property name="factory" type="string"></property> <property name="price" type="double"></property> </class>
2、配置文件
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd" > <hibernate-configuration> <session-factory> <property name="connection.url"> jdbc:mysql://localhost:3306/hibernate </property> <property name="connection.driver_class"> com.mysql.jdbc.Driver </property> <property name="connection.username">root</property> <property name="connection.password">123456</property> <!-方言- <property name="dialect"> org.hibernate.dialect.MySQLDialect </property> <!-在控制台显示sql语句- <property name="show_sql">true</property> <!-sql语句格式化- <property name="format_sql">true</property> <!-建表的方式- <prrperty name=” hbm2ddl.auto”>update</property> <!-连接映射文件- <mapping resource="com/creasoft/entity2/Customer.hbm.xml" /> <mapping resource="com/creasoft/entity2/VipCard.hbm.xml" /> </session-factory> </hibernate-configuration>
3、hibernate的工具类
package com.creasoft.util;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
public class Hibernateutil {
private static SessionFactory sessionFactory ;
//私有的构造方法，防止用户直接new
private Hibernateutil(){
}
//获取sessionfactory
public static SessionFactory getsessionFactory(){
if(sessionFactory == null || sessionFactory.isClosed()){
sessionFactory = new Configuration().configure().buildSessionFactory();
}
return sessionFactory;
}
//打开一个session
public static Session getSession(){
return getsessionFactory().openSession();
}
//关闭session
public static void close(){
getSession().close();
}
}
4、创建表
package com.creasoft.util;
import org.hibernate.cfg.Configuration;
import org.hibernate.tool.hbm2ddl.SchemaExport;
public class CreateTable {
public static void main(String[] args) {
//读取配置文件
Configuration cfg = new Configuration().configure();
System.out.println("a");
SchemaExport schemaExport = new SchemaExport(cfg);
System.out.println("b");
schemaExport.create(true, true);
System.out.println("c");
}
}
5、一对多单向关联
实例：顾客—订单
1）实体类
a、一
package com.creasoft.entity;
import java.util.HashSet;
import java.util.Set;
public class Customer {
private long cid;
private String customerName;
private String gender;
//构造方法
public Customer(String customerName, String gender) {
super();
this.customerName = customerName;
this.gender = gender;
}
public Customer(long cid, String customerName, String gender,
Set<CustomerOrder> sustomerOrders) {
super();
this.cid = cid;
this.customerName = customerName;
this.gender = gender;
this.sustomerOrders = sustomerOrders;
}
public Customer() {
super();
}
//标准的set、get方法
public long getCid() {
return cid;
}
public void setCid(long cid) {
this.cid = cid;
}
public String getCustomerName() {
return customerName;
}
public void setCustomerName(String customerName) {
this.customerName = customerName;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
b、多实体类：把一的所有的属性都要包含进来
package com.creasoft.entity;
public class CustomerOrder {
private long uid;
private String product;
private Customer customer;
public CustomerOrder(String product, Customer customer) {
super();
this.product = product;
this.customer = customer;
}
public CustomerOrder() {
super();
}
public long getUid() {
return uid;
}
public void setUid(long uid) {
this.uid = uid;
}
public String getProduct() {
return product;
}
public void setProduct(String product) {
this.product = product;
}
public Customer getCustomer() {
return customer;
}
public void setCustomer(Customer customer) {
this.customer = customer;
}
}
2)映射文件
A、一的映射文件：一般的映射文件一样
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.creasoft.entity.Customer" table="customer">
<id name="cid" type="long">
<generator class="identity"></generator>
</id>
<property name="customerName" type="string" not-null="true"/>
<property name="gender" type="string" length="2"></property>
</class>
</hibernate-mapping>
B、多：自己的基本属性和一般的映射文件一样，复杂属性放到<many-to-one>的标签，其他的都一样
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.creasoft.entity.CustomerOrder" table="customer_order">
<id name="uid" type="long">
<generator class="identity"></generator>
</id>
<property name="product" type="string" not-null="true"/>
<many-to-one name="customer"
class="com.creasoft.entity.Customer"
not-null="true"
column="customer_id"
cascade="delete"
></many-to-one>
</class>
</hibernate-mapping>
1.1 3)插入一条数据:先要保存一的那一边的实体类
Session session = Hibernateutil.getSession();
//开始事务
Transaction tsaction = session.beginTransaction();
Customer cs = new Customer("chen","m");
CustomerOrder so = new CustomerOrder("手机",cs);
session.save(cs);
session.save(so);
//提交事务
tsaction.commit();
//关闭session
session.close();
6、一对多的双向关联
1）实体类
A、一：与单向关联相比多了一个集合
package com.creasoft.entity;
import java.util.HashSet;
import java.util.Set;
public class Customer {
private long cid;
private String customerName;
private String gender;
private Set<CustomerOrder> sustomerOrders = new HashSet<CustomerOrder>();
public Customer(String customerName, String gender) {
super();
this.customerName = customerName;
this.gender = gender;
}
public Customer(long cid, String customerName, String gender,
Set<CustomerOrder> sustomerOrders) {
super();
this.cid = cid;
this.customerName = customerName;
this.gender = gender;
this.sustomerOrders = sustomerOrders;
}
public Customer() {
super();
}
public long getCid() {
return cid;
}
public void setCid(long cid) {
this.cid = cid;
}
public String getCustomerName() {
return customerName;
}
public void setCustomerName(String customerName) {
this.customerName = customerName;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Set<CustomerOrder> getSustomerOrders() {
return sustomerOrders;
}
public void setSustomerOrders(Set<CustomerOrder> sustomerOrders) {
this.sustomerOrders = sustomerOrders;
}
}
B、多的实体类不变
package com.creasoft.entity;
public class CustomerOrder {
private long uid;
private String product;
private Customer customer;
public CustomerOrder(String product, Customer customer) {
super();
this.product = product;
this.customer = customer;
}
public CustomerOrder() {
super();
}
public long getUid() {
return uid;
}
public void setUid(long uid) {
this.uid = uid;
}
public String getProduct() {
return product;
}
public void setProduct(String product) {
this.product = product;
}
public Customer getCustomer() {
return customer;
}
public void setCustomer(Customer customer) {
this.customer = customer;
}
}
1.2 2）映射文件
1.2.1 A、一：把集合放入set标签中，set标签中还增了一个<one-to-many>标签
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.creasoft.entity.Customer" table="customer">
<id name="cid" type="long">
<generator class="identity"></generator>
</id>
<property name="customerName" type="string" not-null="true"/>
<property name="gender" type="string" length="2"></property>
<!-- 双向的关联 ,key column的值一定要与CustomerOder.hbm.xml中的外键的值要一样 。name放的是集合属性
inverse="true",表示多的一方不必要在等一这边操作完，这的效率要高-->
<set name="sustomerOrders" inverse="true">
<key column="customer_id"></key>
<one-to-many class="com.creasoft.entity.CustomerOrder"/>
</set>
</class>
</hibernate-mapping>
1.2.2 B、多：与单向的一样
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.creasoft.entity.CustomerOrder" table="customer_order">
<id name="uid" type="long">
<generator class="identity"></generator>
</id>
<property name="product" type="string" not-null="true"/>
<many-to-one name="customer"
class="com.creasoft.entity.Customer"
not-null="true"
column="customer_id"
cascade="delete"
></many-to-one>
</class>
</hibernate-mapping>
1.3 3)插入一条数据:先要保存一的那一边的实体类
Session session = Hibernateutil.getSession();
//开始事务
Transaction tsaction = session.beginTransaction();
Customer cs = new Customer();
cs.setCustomerName("chen");
cs.setGender("m");
CustomerOrder co = new CustomerOrder("sdf",cs);
CustomerOrder ct = new CustomerOrder("d",cs);
cs.getSustomerOrders().add(co);
cs.getSustomerOrders().add(ct);
session.save(cs);
session.save(co);
session.save(ct);
//提交事务
tsaction.commit();
//关闭session
session.close();
7、一对一
1）实体类
A
package com.creasoft.entity2;
public class Customer {
private long cid;
private String customerName;
private VipCard vipcard;
/*
* 构造方法
*/
public Customer() {
super();
}
public Customer(String customerName, VipCard vipcard) {
super();
this.customerName = customerName;
this.vipcard = vipcard;
}
/*
* 标准的get、set方法
*/
public long getCid() {
return cid;
}
public void setCid(long cid) {
this.cid = cid;
}
public String getCustomerName() {
return customerName;
}
public void setCustomerName(String customerName) {
this.customerName = customerName;
}
public VipCard getVipcard() {
return vipcard;
}
public void setVipcard(VipCard vipcard) {
this.vipcard = vipcard;
}
}
B、
package com.creasoft.entity2;
public class VipCard {
private long vid;
private float discount;
private Customer customer;
public VipCard() {
super();
}
public VipCard(float discount, Customer customer) {
super();
this.discount = discount;
this.customer = customer;
}
public long getVid() {
return vid;
}
public void setVid(long vid) {
this.vid = vid;
}
public float getDiscount() {
return discount;
}
public void setDiscount(float discount) {
this.discount = discount;
}
public Customer getCustomer() {
return customer;
}
public void setCustomer(Customer customer) {
this.customer = customer;
}
2）映射文件
A、主导类的映射文件：<one-to-one>
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.creasoft.entity2.Customer" table="vcustomer">
<id name ="cid" type="long">
<generator class="identity"></generator>
</id>
<property name="customerName" type="string"></property>
<one-to-one name="vipcard"
class="com.creasoft.entity2.VipCard"
cascade="all"></one-to-one>
</class>
</hibernate-mapping>
B、
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.creasoft.entity2.VipCard" table="vipcard">
<id name="vid" type="long">
<generator class="foreign">
<!—customer必须与vipcard类中的属性名相同
<param name="property">customer</param>
</generator>
</id>
<!-- constrained为true表示name既是主键又是外键 -->
<property name="discount" type="float"></property>
<one-to-one name="customer"
constrained="true"
class="com.creasoft.entity2.Customer"
cascade="save-update"></one-to-one>
</class>
</hibernate-mapping>
1.4 3)插入一条数据
Session session = Hibernateutil.getSession();
//开始事务
Transaction tsaction = session.beginTransaction();
//数据的操作
Customer cs = new Customer();
cs.setCustomerName("chen");
VipCard vc = new VipCard();
vc.setDiscount(0.8f);
vc.setCustomer(cs);
cs.setVipcard(vc);
session.save(cs);
//提交事务
tsaction.commit();
//关闭session
session.close();
}
8、多对多
1）实体类
A、多
package com.creasoft.entity3;
import java.util.HashSet;
import java.util.Set;
public class Customer {
private long cid;
private String customerName;
private Set<Address> addresses = new HashSet<Address>();
public Customer() {
super();
}
public Customer(String customerName, Set<Address> addresses) {
super();
this.customerName = customerName;
this.addresses = addresses;
}
public long getCid() {
return cid;
}
public void setCid(long cid) {
this.cid = cid;
}
public String getCustomerName() {
return customerName;
}
public void setCustomerName(String customerName) {
this.customerName = customerName;
}
public Set<Address> getAddresses() {
return addresses;
}
public void setAddresses(Set<Address> addresses) {
this.addresses = addresses;
}
}
B、多
package com.creasoft.entity3;
import java.util.HashSet;
import java.util.Set;
public class Address {
private long aid;
private String addressDetail;
private Set<Customer> customers = new HashSet<Customer>();
public Address() {
super();
}
public Address(String addressDetail, Set<Customer> customers) {
super();
this.addressDetail = addressDetail;
this.customers = customers;
}
public long getAid() {
return aid;
}
public void setAid(long aid) {
this.aid = aid;
}
public String getAddressDetail() {
return addressDetail;
}
public void setAddressDetail(String addressDetail) {
this.addressDetail = addressDetail;
}
public Set<Customer> getCustomers() {
return customers;
}
public void setCustomers(Set<Customer> customers) {
this.customers = customers;
}
}
2）映射文件：
有且只能在一边必须要加上inverse="true"，不然出错
A、set标签中<many-to-many>
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.creasoft.entity3.Customer" table="acutstomer">
<id name="cid" type="long">
<generator class="identity"></generator>
</id>
<property name="customerName" type="string"></property>
<!-- 两边的table，column必须要一致。这边key中column的必须与另一边many-to-many中column-->
<set name="addresses" inverse="true" table="customer_address">
<key column="customerid"></key>
<many-to-many class="com.creasoft.entity3.Address"
column="addressid">
</many-to-many>
</set>
</class>
</hibernate-mapping>
B、set标签中<many-to-many>
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.creasoft.entity3.Address">
<id name="aid">
<generator class="identity"></generator>
</id>
<property name="addressDetail"></property>
<!-- 两边的table，column必须要一致。这边key中column的必须与另一边many-to-many中column-->
<set name="customers" table="customer_address">
<key column="addressid"></key>
<many-to-many class="com.creasoft.entity3.Customer"
column="customerid"></many-to-many>
</set>
</class>
</hibernate-mapping>
3）插入数据库中
把属性都加入两集合中
package com.creasoft.test;
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.Transaction;
import com.creasoft.entity3.Customer;
import com.creasoft.entity3.Address;
import com.creasoft.util.Hibernateutil;
public class Test03 {
public static void main(String[] args) {
Session session =Hibernateutil.getSession();
Transaction ts = session.beginTransaction();
//对数据库的一些操作
Customer cs1 = new Customer();
Customer cs2 = new Customer();
cs1.setCustomerName("盛开");
cs2.setCustomerName("sk");
Address ad1= new Address();
Address ad2 = new Address();
ad1.setAddressDetail("长沙");
ad2.setAddressDetail("香港");
cs1.getAddresses().add(ad1);
cs1.getAddresses().add(ad2);
ad1.getCustomers().add(cs1);
ad1.getCustomers().add(cs2);
ad1s =cs2.getAddresses();
ad1s.add(ad1);
cs2.getAddresses().add(ad2);
ad2.getCustomers().add(cs1);
ad2.getCustomers().add(cs2);
//set集合到customer中
Cs2.setAddresses(ad1s);
session.save(cs1);
session.save(cs2);
session.save(ad1);
session.save(ad2);
ts.commit();
session.close();
}
}
9、 Hibernate对数据库的基本操作依赖的五个核心接口：
Configuration界面：配置Hibernate,预启动Hibernate,创建SessionFactory对象
SessionFactory界面：初始化Hibernate,充当数据源代理,创建Session对象
Session界面：负责保存,更新,删除,加载和查询对象
Transaction界面：管理事务
Query和Criteria界面：执行数据库查询
10、hql
1）、Query接口：生命周期与session绑定
package com.creasoft.test;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import com.creasoft.entity.SCourse;
import com.creasoft.util.Hibernateutil;
public class Test2 {
public static void main(String[] args) {
Session session = Hibernateutil.getSesion();
<!—其中的scourse是类名
Query query = session.createQuery("FROM SCourse");
<!—list只能适用小量的数据，效率比较高，容易产生内存溢出
List<SCourse> c = query.list();
for(SCourse s: c){
System.out.println(s.getCourseName());
}
<!—iterator能查找大量的数据，但效率低
// Iterator<SCourse> iterator = query.iterate();
//
// while(iterator.hasNext()){
// SCourse s = iterator.next();
// System.out.println(s.getCourseName());
// }
session.close();
}
}
2）、增删改查的封装
//增加用户
Static void addUser(User user){
Session s=null;
Transaction tx=null;
Try{
S=Hibernateutil.getSession();
tx=s.beginTransaction();
s.save(User);
tx.commit();
}catch(HibernateException e){
If(tx!=null){
tx.rollback();
throw e;
}finally{
If(s!=null){
s.close();
}
}
}
//修改
public static void update(User user){
Session s=null;
Transaction ts=null;
try{
s=sessionFactory.openSession();
ts=s.beginTransaction();
s.update(user);
ts.commit();
}finally{
if(s!=null){
s.close();
}
}
}
//删除
public static void delete(User user){
Session s=null;
Transaction ts=null;
try{
s=sessionFactory.openSession();
ts=s.beginTransaction();
s.delete(user);
ts.commit();
}finally{
if(s!=null){
s.close();
}
}
}
2、 查询
1） Hql：是对对象操作，而不是表。
在sql中能用的方法在hql中一定能够使用，只是hql操作的是对象，sql是表。
a、 模糊查询
public List<TicketSite> findByTname(String Tname) {
List<TicketSite> list = new ArrayList<TicketSite>();
Session session = HibernateUtil.getSession();
// TicketSite是一个类名，而不是表名
String hql = "from TicketSite t where t.train.Tname like ‘%"+Tname+“%’”;
Query query = session.createQuery(hql);
query.setString(0, Tname);
list = query.list();
return list;
}
1.4.1.1 B、条件查询
1.4.2 //根据站名查询
public List<TicketSite> findBySites(String start, String end) {
List<TicketSite> list = new ArrayList<TicketSite>();
Session session = HibernateUtil.getSession();
String hql = "from TicketSite where siteFrom=? and siteTo=?";
Query query = session.createQuery(hql);
query.setString(0, start);
query.setString(1,end);
list = query.list();
return list;
}
//根据车次查询
public List<TicketSite> findByTname(String Tname) {
List<TicketSite> list = new ArrayList<TicketSite>();
Session session = HibernateUtil.getSession();
String hql = "from TicketSite t where t.train.Tname=?";
Query query = session.createQuery(hql);
query.setString(0, Tname);
list = query.list();
return list;
}
1.4.3 返回的是一个实体
//根据订单的编号查找订单的信息
public Order findOrder(long orderNumberd) {
Order od = new Order();
Session session = HibernateUtil.getSession();
Transaction ts = session.beginTransaction();
String hql="from Order where orderNumberd = ?";
Query query = session.createQuery(hql);
query.setLong(0, orderNumberd);
od = (Order)query.uniqueResult();
ts.commit();
session.close();
return od;
}
2） get、load
session.get(Clazz, id);
session.load(Clazz, id);
1.5 级联删除
删除多的一边,先要使一的一边为空.
1.5.1 一的那边
//根据id，修改订单详细
public boolean updateOrderProduct(OrderProduct op){
boolean flag =false;
Session session = HibernateUtil.getSession();
Transaction ts = session.beginTransaction();
System.out.println(op.getId());
op = (OrderProduct)session.get(OrderProduct.class,op.getId());
op.setOrder(null);
session.update(op);
flag = true;
ts.commit();
session.close();
return flag;
}
1.5.2 多
//删除订单中的商品
public boolean delete(OrderProduct op){
boolean flag = false;
Session session = HibernateUtil.getSession();
Transaction ts = session.beginTransaction();
op = (OrderProduct)session.get(OrderProduct.class, op.getId());
session.delete(op);
flag = true;
ts.commit();
session.close();
return flag;
}
1.5.3 业务层
//删除订单中的商品
public boolean delete(OrderProduct op){
boolean flag = false;
IOrderDao orderDao = new OrderDaoImpl();
orderDao.updateOrderProduct(op);
flag = orderDao.delete(op);
return flag;
}
1.6 级联插入
先要插入多的一面
1.6.1 Dao层
1.6.1.1 查找到一的实体
//根据id查找订单信息
public Order findOd(long id){
Order od = new Order();
Session session = HibernateUtil.getSession();
String hql = "from Order where id = ?";
Query query = session.createQuery(hql);
query.setLong(0, id);
od = (Order)query.uniqueResult();
session.close();
return od;
}
1.6.1.2 多
//插入操作历史
public boolean insertOrderHistory(Order od, OrderHistory oh){
boolean flag = false;
Session session = HibernateUtil.getSession();
Transaction ts = session.beginTransaction();
oh.setOd(od);
session.save(oh);
session.update(od);
flag = true;
ts.commit();
session.close();
return flag;
}
1.6.2 业务层
//判断插入的订单操作历史是否成功
public boolean insertOrderHistory(long id, OrderHistory oh){
boolean flag = false;
IOrderDao orderDao = new OrderDaoImpl();
//取得订单
Order od = orderDao.findOd(id);
flag = orderDao.insertOrderHistory(od, oh);
return flag;
}
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发表评论
-
hibernate 的加载
2012-06-20 22:39 01.lazy应用范围： lazy只有在session打开状态 ... -
hibernate 的加载
2012-06-20 22:39 6521.lazy应用范围： lazy只有在session打开状态 ... -
hibernate的缓存
2012-06-20 22:21 6511.配置二级缓存 a.具体的配置位置位于hibernate. ... -
cascade 和inverse
2012-06-20 21:35 633总体上说inverse是指定哪个表作为维护端，cascade则 ... -
Hibernate主键生成策略
2012-06-20 20:32 6941、自动增长identity 适用于MySQL、DB2、M ... -
hibernate 的状态
2012-06-19 19:54 679在Hibernate中有三种状态，对它的深入理解，才能更好的理 ...
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