<?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>        <!-- Database connection settings -->        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>        <property name="connection.url">jdbc:mysql://127.0.0.1/testdb</property>        <property name="connection.username">root</property>        <property name="connection.password"></property>        <!-- JDBC connection pool (use the built-in) -->        <property name="connection.pool_size">1</property>        <!-- SQL dialect -->        <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>        <!-- Enable Hibernate‘s automatic session context management -->        <property name="current_session_context_class">thread</property>        <!-- Disable the second-level cache  -->        <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>        <!-- Echo all executed SQL to stdout -->        <property name="show_sql">true</property>        <!-- Drop and re-create the database schema on startup -->        <property name="hbm2ddl.auto">update</property>                <mapping class="com.my.bean.User"/>        <mapping class="com.my.bean.UserCard"/>        <mapping class="com.my.bean.UserInfo"/>    </session-factory></hibernate-configuration>

package com.my.dao.util;import org.hibernate.SessionFactory;import org.hibernate.boot.registry.StandardServiceRegistryBuilder;import org.hibernate.cfg.Configuration;public class HibernateUtil {    private static final SessionFactory sessionFactory = buildSessionFactory();    private static SessionFactory buildSessionFactory() {        try {            // Create the SessionFactory from hibernate.cfg.xml            Configuration configuration = new Configuration();            return configuration.configure().buildSessionFactory(                    new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build());        } catch (Throwable ex) {            // Make sure you log the exception, as it might be swallowed            System.err.println("Initial SessionFactory creation failed." + ex);            throw new ExceptionInInitializerError(ex);        }    }    public static SessionFactory getSessionFactory() {        return sessionFactory;    }    }

package com.my.bean;import java.util.Date;import javax.persistence.*;@Entity@Table(name="user")public class User {    @Id @GeneratedValue @Column(name="user_id", nullable=false)    private long userID;        @Column(name="user_name", length=100, nullable=false)    private String userName;        @Column(name="create_time", nullable=false)    private Date createTime;        @OneToOne(mappedBy="user")    private UserCard userCard;        @OneToOne(cascade=CascadeType.ALL)    @PrimaryKeyJoinColumn    private UserInfo userInfo;    public long getUserID() {        return userID;    }    public void setUserID(long userID) {        this.userID = userID;    }    public String getUserName() {        return userName;    }    public void setUserName(String userName) {        this.userName = userName;    }    public Date getCreateTime() {        return createTime;    }    public void setCreateTime(Date createTime) {        this.createTime = createTime;    }    public UserCard getUserCard() {        return userCard;    }    public void setUserCard(UserCard userCard) {        this.userCard = userCard;    }}

package com.my.bean;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.GenerationType;import javax.persistence.Id;import javax.persistence.JoinColumn;import javax.persistence.OneToOne;import javax.persistence.Table;@Entity@Table(name="user_card")public class UserCard {    @Id    @GeneratedValue(strategy=GenerationType.IDENTITY)    @Column(name="card_id", nullable=false)    private long cardID;        @OneToOne    @JoinColumn(name="user_id")    private User user;        @Column(name="card_name", nullable=false)    private String cardName;        public long getCardID() {        return cardID;    }    public void setCardID(long cardID) {        this.cardID = cardID;    }    public User getUser() {        return user;    }    public void setUser(User user) {        this.user = user;    }    public String getCardName() {        return cardName;    }    public void setCardName(String cardName) {        this.cardName = cardName;    }}

package com.my.bean;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.Id;import javax.persistence.OneToOne;import javax.persistence.Table;import org.hibernate.annotations.GenericGenerator;import org.hibernate.annotations.Parameter;@Entity@Table(name="user_info")public class UserInfo {    @Id    @GeneratedValue(generator="userInfoForeignKey")    @GenericGenerator(name="userInfoForeignKey", strategy="foreign", parameters=@Parameter(name="property", value="http://www.mamicode.com/user"))    @Column(name="user_id", nullable=false)    private long userID;        @Column(name="message", nullable=false)    private String Message;        @OneToOne(mappedBy="userInfo")    private User user;    public long getUserID() {        return userID;    }    public void setUserID(long userID) {        this.userID = userID;    }    public String getMessage() {        return Message;    }    public void setMessage(String message) {        Message = message;    }    public User getUser() {        return user;    }    public void setUser(User user) {        this.user = user;    }}

package com.my.init;import java.util.Date;import org.hibernate.Session;import org.hibernate.Transaction;import com.my.bean.User;import com.my.bean.UserCard;import com.my.bean.UserInfo;import com.my.dao.util.HibernateUtil;public class Test {    public static void main(String[] args) {        Session session = HibernateUtil.getSessionFactory().openSession();        Transaction tx = session.beginTransaction();                try {            //---------------------------------------------------------            // The first method            //---------------------------------------------------------            // add user            User user = new User();            user.setUserName("Robin");            user.setCreateTime(new Date());                        // add user card            UserCard userCard = new UserCard();            userCard.setCardName("BBC");                        // add user card to user object            user.setUserCard(userCard);            userCard.setUser(user);                        //---------------------------------------------------------            // The second method            //---------------------------------------------------------            UserInfo userInfo = new UserInfo();            userInfo.setMessage("Message");            userInfo.setUser(user);                        //---------------------------------------------------------            // save            //---------------------------------------------------------            session.save(user);            session.save(userCard);            session.save(userInfo);                        tx.commit();        } catch (Exception e) {            tx.rollback();            e.printStackTrace();        }                session.close();    }}