Hibernate的写法总结

• 普通表操作

　　　　普通操作莫过于CRUD，建好表了之后对表的数据进行操作。详见代码。　　　　

package package2;



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

public class HibernateExecute {

    public static void main(String[] args) {
        HibernateController hc=new HibernateController();
        persion toadd=new persion();
        toadd.setId(6);
        toadd.setName("lkxj");
        hc.update(toadd);
    }

}
class HibernateUtil{
    private static SessionFactory ssf;
    static{
        Configuration cfg=new Configuration().configure();
        ssf=cfg.buildSessionFactory();
    }
    public static Session getSession(){
        Session session=ssf.openSession();
        return session;
    }
    public static void closeSession(Session session){
        session.close();
    }
}
class HibernateController implements DAOInterface{

    // 添加信息
    @Override
    public void add(persion p) {
        Session session=HibernateUtil.getSession();
        Transaction transaction=session.beginTransaction();
        try{
            session.save(p);
            transaction.commit();
        }catch (Exception e) {
            // TODO: handle exception
            transaction.rollback();
        }finally {
            HibernateUtil.closeSession(session);
        }
    }
    // 删除信息
    @Override
    public void delete(persion p) {
        // TODO Auto-generated method stub
        Session session=HibernateUtil.getSession();
        Transaction transaction=session.beginTransaction();
        try{
            session.delete(p);
            transaction.commit();
        }catch (Exception e) {
            // TODO: handle exception
            transaction.rollback();
        }finally {
            HibernateUtil.closeSession(session);
        }
    }
    // 搜寻信息
    @Override
    public persion search(int id) {
        // TODO Auto-generated method stub
        Session session=HibernateUtil.getSession();
        Transaction transaction=session.beginTransaction();
        persion p=null;
        try{
            p=(persion)session.get(persion.class, id);
            transaction.commit();
        }catch (Exception e) {
            // TODO: handle exception
            transaction.rollback();
        }finally {
            HibernateUtil.closeSession(session);
        }
        return p;
    }
    // 更新信息
    @Override
    public void update(persion p) {
        // TODO Auto-generated method stub
        Session session=HibernateUtil.getSession();
        Transaction transaction=session.beginTransaction();
        try{
            session.update(p);
            transaction.commit();
        }catch (Exception e) {
            // TODO: handle exception
            transaction.rollback();
        }finally {
            HibernateUtil.closeSession(session);
        }
    }
    
}

　　　　bean类如下

package package2;

public class persion {
    int id;
    String name;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    
}

　　　　persion.hbm.xml

<?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 2016-7-20 15:57:35 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="package2.persion" table="PERSION">
        <id name="id" type="int">
            <column name="id" />
            <generator class="assigned" />
        </id>
        <property name="name" type="java.lang.String">
            <column name="name" />
        </property>
    </class>
</hibernate-mapping>

　　　　在hiberna.cfg.xml末尾添加一行

        <mapping resource="package2/persion.hbm.xml" />

• 映射关系

　　　　一对一映射：比如一个用户只有一个地址。实现的方式有两种，一，主键关联；二，外键关联。

　　　　主键关联就是两个表的主键其中一个为另外一个表的外键。比如user表的主键，为address表的外键，这个address的外键正好就是它这个表的主键。user为主表，address为从表。address的外键引用的时user的主键。在下面的设计中，是user类为address的从表，user的生成策略为foreign，表示主键由关联类产生。

　　　　User.java

package HibernateRelation;
//一个用户只有一个地址
public class User {
	private int userid;
	private String name;
	private String password;
	private Address address;
	public User(){
		
	}
	public User(String name,String password,Address address){
		this.name=name;
		this.password=password;
		this.address=address;
		
	}
	public int getUserid() {
		return userid;
	}
	public void setUserid(int userid) {
		this.userid = userid;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public Address getAddress() {
		return address;
	}
	public void setAddress(Address address) {
		this.address = address;
	}
	
}

　　　　Address.java

package HibernateRelation;

public class Address {
	private int addressid;
	private String addressinfo;
	public Address(int addressid,String addressinfo){
		this.addressid=addressid;
		this.addressinfo=addressinfo;
	}
	public Address(){
		
	}
	public int getAddressid() {
		return addressid;
	}
	public void setAddressid(int addressid) {
		this.addressid = addressid;
	}
	public String getAddressinfo() {
		return addressinfo;
	}
	public void setAddressinfo(String addressinfo) {
		this.addressinfo = addressinfo;
	}
	
}

　　　　User.hbm.xml

<?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 2016-8-16 14:48:03 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="HibernateRelation.User" table="USER">
        <id name="userid" type="int" access="field">
            <column name="USERID" />
            <!--由关联类来生成主键 -->
            <generator class="foreign" >
                <param name="property">address</param>
            </generator>
        </id>
        <property name="name" type="java.lang.String">
            <column name="NAME" />
        </property>
        <property name="password" type="java.lang.String">
            <column name="PASSWORD" />
        </property>
        <!--基于主键的一对一映射-->
        <one-to-one name="address" class="HibernateRelation.Address" constrained="true">
        </one-to-one>
    </class>
</hibernate-mapping>

　　　　Address.hbm.xml

<?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 2016-8-16 14:48:03 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="HibernateRelation.Address" table="ADDRESS">
        <id name="addressid" type="int" access="field">
            <column name="ADDRESSID" />
            <generator class="identity" /><!--主键生成策略-->
        </id>
        <property name="addressinfo" type="java.lang.String">
            <column name="ADDRESSINFO" />
        </property>
    </class>
</hibernate-mapping>

　　　　惯例，在总配置文件中添加映射，和自动建表配置。

<property name="hibernate.hbm2ddl.auto">update</property>        
<mapping resource="HibernateRelation/User.hbm.xml" />    
<mapping resource="HibernateRelation/Address.hbm.xml" />

　　　　在这里可以先建表，也可以不用建表，表结构和你写的类关系类似。遇到一个错误，在one-to-one的标签里添加了column这个属性，会导致一个异常。因为是工具自动产生的。

　　　　外键关联：一个表中有主键也有外键，外键是另外一个表的主键的引用。

package HibernateRelation;

public class User2 {
	private int userid;
	private String name;
	private String password;
	private Address2 address2;
	
	public Address2 getAddress2() {
		return address2;
	}
	public void setAddress2(Address2 address2) {
		this.address2 = address2;
	}
	public int getUserid() {
		return userid;
	}
	public void setUserid(int userid) {
		this.userid = userid;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	
}

　　

package HibernateRelation;

public class Address2 {
	private int addressid;
	private String addressinfo;
	public int getAddressid() {
		return addressid;
	}
	public void setAddressid(int addressid) {
		this.addressid = addressid;
	}
	public String getAddressinfo() {
		return addressinfo;
	}
	public void setAddressinfo(String addressinfo) {
		this.addressinfo = addressinfo;
	}
	
}

<?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 2016-8-16 16:49:52 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="HibernateRelation.User2" table="USER2">
        <id name="userid" type="int">
            <column name="USERID" />
            <generator class="identity" />
        </id>
        <property name="name" type="java.lang.String">
            <column name="NAME" />
        </property>
        <property name="password" type="java.lang.String">
            <column name="PASSWORD" />
        </property>
        <many-to-one name="address2" class="HibernateRelation.Address2" fetch="join" unique="true">
            <column name="ADDRESS2" />
        </many-to-one>
    </class>
</hibernate-mapping>

　　　　这个配置文件，主要是写成many-to-one，unique设置为true。column的name为属性名，关联类配置在class中，在表中建立的外键名column中可以设置。

<?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 2016-8-16 16:49:52 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="HibernateRelation.Address2" table="ADDRESS2">
        <id name="addressid" type="int">
            <column name="ADDRESSID" />
            <generator class="identity" />
        </id>
        <property name="addressinfo" type="java.lang.String">
            <column name="ADDRESSINFO" />
        </property>
    </class>
</hibernate-mapping>

　　　　一对多映射：一个用户可以有多个收货地址，在这个设计中，官方说法是在多的一方加入外键，并指向一的一方。就是在address表中加入一个用户id，user的id为地址的识别码，id=2的用户在address表中可以有多条地址记录，他们隶属于外键id=2这个用户之下。

　　　　实现方法就是在bean类中加入一个集合set，然后生成xml的时候会自动配置。

package HibernateRelation;

import java.util.HashSet;
import java.util.Set;
//一个用户对应多个地址
public class User1 {
	private int userid;
	private String name;
	private String password;
	private Set<Address1> addresses=new HashSet<Address1>();
	public User1(){
		
	}
	public User1(int userid,String name,String password){
		this.userid=userid;
		this.name=name;
		this.password=password;	
	}
	public int getUserid() {
		return userid;
	}
	public void setUserid(int userid) {
		this.userid = userid;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public Set<Address1> getAddresses() {
		return addresses;
	}
	public void setAddresses(Set<Address1> addresses) {
		this.addresses = addresses;
	}
	
}

　　

<?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 2016-8-16 15:56:52 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="HibernateRelation.User1" table="USER1">
        <id name="userid" type="int">
            <column name="USERID" />
            <generator class="identity" />
        </id>
        <property name="name" type="java.lang.String">
            <column name="NAME" />
        </property>
        <property name="password" type="java.lang.String">
            <column name="PASSWORD" />
        </property>
        <set name="addresses" table="ADDRESS1" inverse="false" lazy="true">
            <key>
                <column name="USERID" />
            </key>
            <one-to-many class="HibernateRelation.Address1" />
        </set>
    </class>
</hibernate-mapping>

package HibernateRelation;

public class Address1 {
	private int addressid;
	private String addressinfo;
	public int getAddressid() {
		return addressid;
	}
	public void setAddressid(int addressid) {
		this.addressid = addressid;
	}
	public String getAddressinfo() {
		return addressinfo;
	}
	public void setAddressinfo(String addressinfo) {
		this.addressinfo = addressinfo;
	}
	
}

<?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 2016-8-16 15:56:52 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="HibernateRelation.Address1" table="ADDRESS1">
        <id name="addressid" type="int">
            <column name="ADDRESSID" />
            <generator class="identity" />
        </id>
        <property name="addressinfo" type="java.lang.String">
            <column name="ADDRESSINFO" />
        </property>
    </class>
</hibernate-mapping>

　　　　多对多映射：多个用户对应多个地址，这里是单向的多对多，也就是一个用户对应多个地址，一个地址对应多个用户，他们需要有一个中间表，来转换映射。

package HibernateRelation;

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

public class User3 {
	private int userid;
	private String name;
	private String password;
	private Set<Address3> address3s=new HashSet<Address3>();
	public int getUserid() {
		return userid;
	}
	public void setUserid(int userid) {
		this.userid = userid;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public Set<Address3> getAddress3s() {
		return address3s;
	}
	public void setAddress3s(Set<Address3> address3s) {
		this.address3s = address3s;
	}
	
}

　　

package HibernateRelation;

public class Address3 {
	private int addressid;
	private String addressinfo;
	
	public int getAddressid() {
		return addressid;
	}
	public void setAddressid(int addressid) {
		this.addressid = addressid;
	}
	public String getAddressinfo() {
		return addressinfo;
	}
	public void setAddressinfo(String addressinfo) {
		this.addressinfo = addressinfo;
	}
	
}

　　　　在这个配置中，需要修改set标签的table属性，改为一个新表，它会生成一个中间表。自动生成时候没有修改报了一个映射异常。

<?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 2016-8-16 18:35:47 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="HibernateRelation.User3" table="USER3">
        <id name="userid" type="int">
            <column name="USERID" />
            <generator class="identity" />
        </id>
        <property name="name" type="java.lang.String">
            <column name="NAME" />
        </property>
        <property name="password" type="java.lang.String">
            <column name="PASSWORD" />
        </property>
        <set name="address3s" table="USER3_ADDRESS3" inverse="false" lazy="true">
            <key>
                <column name="USERID" />
            </key>
            <many-to-many class="HibernateRelation.Address3" column="ADDRESSID"/>
        </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 2016-8-16 18:35:47 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="HibernateRelation.Address3" table="ADDRESS3">
        <id name="addressid" type="int">
            <column name="ADDRESSID" />
            <generator class="identity" />
        </id>
        <property name="addressinfo" type="java.lang.String">
            <column name="ADDRESSINFO" />
        </property>
    </class>
</hibernate-mapping>

• 后记

　　　　余下细节以后补充。