5、hibernate第五课

Hibernate一对多关系操作

1.先创建 3个实体类

package com.zking.entity;

public class City {
	private String cid;
	private String cname;
	private transient Province province;

	public City() {
		super();
		// TODO Auto-generated constructor stub
	}

	public City(String cid, String cname) {
		super();
		this.cid = cid;
		this.cname = cname;

	}

	public String getCid() {
		return cid;
	}

	public void setCid(String cid) {
		this.cid = cid;
	}

	public String getCname() {
		return cname;
	}

	public void setCname(String cname) {
		this.cname = cname;
	}

	public Province getProvince() {
		return province;
	}

	public void setProvince(Province province) {
		this.province = province;
	}

	@Override
	public String toString() {
		return "City [cid=" + cid + ", cname=" + cname + "]";
	}

}

package com.zking.entity;

import java.util.HashSet;
import java.util.Set;

public class Nation {
	private String nid;
	private String nname;
	private Set<Province> sp = new HashSet<Province>();

	public Nation() {
		super();
	}

	public Nation(String nid, String nname, Set<Province> sp) {
		super();
		this.nid = nid;
		this.nname = nname;
		this.sp = sp;
	}
	public String getNid() {
		return nid;
	}
	public void setNid(String nid) {
		this.nid = nid;
	}

	public String getNname() {
		return nname;
	}

	public void setNname(String nname) {
		this.nname = nname;
	}

	public Set<Province> getSp() {
		return sp;
	}

	public void setSp(Set<Province> sp) {
		this.sp = sp;
	}

	@Override
	public String toString() {
		return "Nation [nid=" + nid + ", nname=" + nname + ", sp=" + sp + "]";
	}

}

package com.zking.entity;

import java.util.HashSet;
import java.util.Set;

public class Province {
	private String pid;
	private String pname;
	private transient Nation nation;

	private Set<City> sc = new HashSet<City>();

	public Province() {
		super();
		// TODO Auto-generated constructor stub
	}

	public Province(String pid, String pname, Nation nation) {
		super();
		this.pid = pid;
		this.pname = pname;
		this.nation = nation;
	}

	public String getPid() {
		return pid;
	}

	public Nation getNation() {
		return nation;
	}

	public void setNation(Nation nation) {
		this.nation = nation;
	}

	public void setPid(String pid) {
		this.pid = pid;
	}

	public String getPname() {
		return pname;
	}

	public void setPname(String pname) {
		this.pname = pname;
	}

	public Set<City> getSc() {
		return sc;
	}

	public void setSc(Set<City> sc) {
		this.sc = sc;
	}

	@Override
	public String toString() {
		return "Province [pid=" + pid + ", pname=" + pname + "]";
	}

}

2.hibernate.cfg.xml文件配置 

<?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>
		<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
		<property name="hibernate.connection.password">sasa</property>
		<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/books?characterEncoding=utf-8</property>
		<property name="hibernate.connection.username">root</property>

		<property name="show_sql">true</property>
		<property name="format_sql">true</property>

		<mapping resource="com/zking/entity/City.hbm.xml" />
		<mapping resource="com/zking/entity/Province.hbm.xml" />
		<mapping resource="com/zking/entity/Nation.hbm.xml" />
	</session-factory>
</hibernate-configuration>

3.配置City.hbm.xml和Nation.hbm.xml和Province.hbm.xml映射文件 

<?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 2018-9-10 8:47:12 by Hibernate Tools 3.5.0.Final -->
<hibernate-mapping>
	<class name="com.zking.entity.City" table="CITY">
		<id name="cid" type="java.lang.String">
			<column name="CID" />
			<generator class="guid" />
		</id>
		<property name="cname" type="java.lang.String">
			<column name="CNAME" />
		</property>
		<!-- <property name="pid" type="java.lang.String"> -->
		<!-- <column name="PID" /> -->
		<!-- </property> -->

		<many-to-one name="province" class="com.zking.entity.Province"
			column="pid" ></many-to-one>
	</class>
</hibernate-mapping>

<?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 2018-9-10 8:54:51 by Hibernate Tools 3.5.0.Final -->
<hibernate-mapping>
	<class name="com.zking.entity.Nation" table="NATION">
		<id name="nid" type="java.lang.String">
			<column name="NID" />
			<generator class="guid" />
		</id>
		<property name="nname" type="java.lang.String">
			<column name="NNAME" />
		</property>
		<set name="sp" table="PROVINCE" cascade="all-delete-orphan"
			inverse="true" lazy="false">
			<key column="nid"></key>
			<one-to-many class="com.zking.entity.Province" />
		</set>
	</class>
</hibernate-mapping>

<?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 2018-9-10 8:54:51 by Hibernate Tools 3.5.0.Final -->
<hibernate-mapping>
	<class name="com.zking.entity.Province" table="PROVINCE">
		<id name="pid" type="java.lang.String">
			<column name="PID" />
			<generator class="guid" />
		</id>
		<property name="pname" type="java.lang.String">
			<column name="PNAME" />
		</property>
		<many-to-one name="nation" class="com.zking.entity.Nation"
			column="nid" lazy="false"></many-to-one>

		<set name="sc" table="CITY" lazy="false" inverse="true"
			cascade="all-delete-orphan">
			<key column="pid"></key>
			<one-to-many class="com.zking.entity.City" />
		</set>

	</class>
</hibernate-mapping>

4 . 测试类

package com.zking.test;

import java.util.Set;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.junit.Test;

import com.alibaba.fastjson.JSON;
import com.zking.entity.City;
import com.zking.entity.Nation;
import com.zking.entity.Province;

public class TestMany {

	@Test
	public void add() {
		Configuration config = new Configuration().configure();
		SessionFactory sessionFactory = config.buildSessionFactory();
		Session session = sessionFactory.openSession();
		Transaction transaction = session.beginTransaction();
		// 开始创建插入对象的数据对象
		Nation n1 = new Nation();
		n1.setNname("中国");
		// 省份1
		Province p1 = new Province();
		p1.setPname("湖南");
		// 互设
		p1.setNation(n1);
		// 省份2
		Province p2 = new Province();
		p2.setPname("广东");
		// 互设
		p2.setNation(n1);
		// 国家对象里面添加省份的对象
		n1.getSp().add(p1);
		n1.getSp().add(p2);
		// 保存
		session.save(n1);
		transaction.commit();
		session.close();
		sessionFactory.close();
	}

	@Test
	public void query() {
		Configuration config = new Configuration().configure();
		SessionFactory sessionFactory = config.buildSessionFactory();
		Session session = sessionFactory.openSession();
		Nation n1 = session.get(Nation.class, "a566afb7-b4ea-11e8-9945-54e1ad416ca2");
		System.out.println(n1);
		Province p1 = session.get(Province.class, "a56941f6-b4ea-11e8-9945-54e1ad416ca2");
		System.out.println(p1);
		session.close();
		sessionFactory.close();
	}

	@Test
	public void query2() {
		Configuration config = new Configuration().configure();
		SessionFactory sessionFactory = config.buildSessionFactory();
		Session session = sessionFactory.openSession();
		Province p1 = session.get(Province.class, "a56941f6-b4ea-11e8-9945-54e1ad416ca2");
		// 城市
		City c1 = new City();
		c1.setCname("长沙");
		c1.setProvince(p1);
		City c2 = new City();
		c2.setCname("株洲");
		c2.setProvince(p1);
		City c3 = new City();
		c3.setCname("湘潭");
		c3.setProvince(p1);
		session.save(c1);
		session.save(c2);
		session.save(c3);
		session.beginTransaction().commit();
		session.close();
		sessionFactory.close();
	}

	@Test
	public void query3() {
		Configuration config = new Configuration().configure();
		SessionFactory sessionFactory = config.buildSessionFactory();
		Session session = sessionFactory.openSession();
		Province p1 = session.get(Province.class, "a56941f6-b4ea-11e8-9945-54e1ad416ca2");
		System.out.println(p1.getPname());
		Set<City> sc = p1.getSc();
		for (City city : sc) {
			System.out.println(city);
		}
		session.close();
		sessionFactory.close();
	}

	@Test
	public void query4() {
		Configuration config = new Configuration().configure();
		SessionFactory sessionFactory = config.buildSessionFactory();
		Session session = sessionFactory.openSession();
		Nation n1 = session.get(Nation.class, "a566afb7-b4ea-11e8-9945-54e1ad416ca2");
		System.out.println(n1.getNname());
		// 省份
		Set<Province> sp = n1.getSp();
		for (Province province : sp) {
			System.out.println(province);
		}
		String str = JSON.toJSONString(n1);
		System.out.println(str);
		session.close();
		sessionFactory.close();
	}

	@Test
	public void delete() {
		Configuration config = new Configuration().configure();
		SessionFactory sessionFactory = config.buildSessionFactory();
		Session session = sessionFactory.openSession();
		Nation n1 = session.get(Nation.class, "a566afb7-b4ea-11e8-9945-54e1ad416ca2");
		session.delete(n1);
		session.beginTransaction().commit();
		session.close();
		sessionFactory.close();
	}

	@Test
	public void add2() {
		Configuration config = new Configuration().configure();
		SessionFactory sessionFactory = config.buildSessionFactory();
		Session session = sessionFactory.openSession();
		//国家
		Nation n1=new Nation();
		n1.setNname("中国");
		//省份
		Province p1=new Province();
		p1.setPname("湖南");
		Province p2=new Province();
		p2.setPname("广东");
		//城市
		City c1=new City();
		c1.setCname("长沙");
		City c2=new City();
		c2.setCname("株洲");
		City c3=new City();
		c3.setCname("湘潭");
		//互设
		n1.getSp().add(p1);
		n1.getSp().add(p2);
		//省份里面设置国家
		p1.setNation(n1);
		p2.setNation(n1);
		//省份里面加城市
		p1.getSc().add(c1);
		p1.getSc().add(c2);
		p1.getSc().add(c3);
		//城市里面设置省份
		c1.setProvince(p1);
		c2.setProvince(p1);
		c3.setProvince(p2);
		session.save(n1);
		session.beginTransaction().commit();
		session.close();
		sessionFactory.close();
	}
}