Hibernate学习（一）创建数据表

（1）生成数据库表的创建：

            // 默认读取hibernate.cfg.xml文件  
            Configuration cfg = new Configuration().configure();  
              
            // 生成并输出sql到文件（当前目录）和数据库  
            SchemaExport export = new SchemaExport(cfg);  
              
            // 创建表结构，第一个true 表示在控制台打印sql语句，第二个true 表示导入sql语句到数据库
            export.create(true, true); 

(2)Hibernate.cfg.xml文件

<?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>
    <!-- 必须去配置的属性 -->
    <!-- 配置数据库连接的基本信息: -->
    <property name="hibernate.connection.driver_class">
        com.mysql.jdbc.Driver
    </property>
    <property name="hibernate.connection.url">
        jdbc:mysql:///hibernate
    </property>
    <property name="hibernate.connection.username">root</property>
    <property name="hibernate.connection.password">123456</property>
    <!-- Hibernate的方言 -->
    <!-- 生成底层SQL不同的 -->
    <property name="hibernate.dialect">
        org.hibernate.dialect.MySQLDialect
    </property>

    <!-- 可选的属性 -->
    <!-- 显示SQL -->
    <property name="hibernate.show_sql">true</property>
    <!-- 格式化SQL -->
    <property name="hibernate.format_sql">true</property>
    <!-- hbm:映射 to DDL: create drop alter -->
    <property name="hibernate.hbm2ddl.auto">update</property>


    <!-- 通知Hibernate加载那些映射文件 -->
    <mapping resource="cn/lonecloud/domain/User.hbm.xml" />
    <mapping resource="cn/lonecloud/domain/Customer.hbm.xml" />
    <mapping resource="cn/lonecloud/domain/Order.hbm.xml" />

</session-factory>
</hibernate-configuration>

(3)log4j.properties文件

### direct log messages to stdout ###
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.err
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

### direct messages to file mylog.log ###
log4j.appender.file=org.apache.log4j.FileAppender
log4j.appender.file.File=c:mylog.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

### set log levels - for more verbose logging change 'info' to 'debug' ###

log4j.rootLogger=off, stdout 

（4）User.java

package cn.lonecloud.domain;

import java.io.Serializable;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Date;

public class User implements Serializable,Cloneable {
   
      private String id;
      private String name;
      private String password;
      private Date birthday;
      public User(){
          System.out.println("user");
      }
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    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 Date getBirthday() {
        return birthday;
    }
    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }
    @Override
    public  Object clone() throws CloneNotSupportedException {
         Class clazz = User.class;
         User user =null;
         try {
             user = (User)clazz.newInstance();
             /*user.setBirthday(this.birthday);
             user.setId(this.id);
             user.setPassword(this.password);
             user.setName(this.name);*/
             Field[] declaredFields = clazz.getDeclaredFields();
             for(Field field :declaredFields){
                  Class<?> parameterTypes = field.getType();
                  String fieldName = field.getName();
                  String methodName = "set"+fieldName.substring(0,1).toUpperCase()+field.getName().substring(1);
                  Method method = clazz.getDeclaredMethod(methodName, parameterTypes);
                  field.setAccessible(true);
                  method.invoke(user,field.get(this));
             }
             return user;
        } catch (Exception e) {
            e.printStackTrace();
        } 
         return null;
    }
      
      
}

(5).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">  
<hibernate-mapping package="cn.lonecloud.domain" >  
    <class name="User" table="t_user"  select-before-update="false">  
        <!--hibernate为我们生成主键id-->  
        <id name="id">  
            <generator class="uuid" />  
        </id>  
          
        <!--默认把类的变量映射为相同名字的表列，当然我们使用column属性修改表字段-->  
        <property name="name" column="names"></property>  
        <property name="password"></property> 
        <property name="birthday" type="date"></property> <!--当为日期类型的时候标明date类型-->
        
    </class>  
</hibernate-mapping>

 6.Customer.java

package cn.lonecloud.domain;

import java.io.Serializable;
import java.util.HashSet;
import java.util.Set;

public class Customer implements Serializable {

    private String id;

    private String customerName;
    
    private Set<Order> orders = new HashSet<Order>();

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getCustomerName() {
        return customerName;
    }

    public void setCustomerName(String customerName) {
        this.customerName = customerName;
    }

    public Set<Order> getOrders() {
        return orders;
    }

    public void setOrders(Set<Order> orders) {
        this.orders = orders;
    }

    
}

7.Customer.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">  
<hibernate-mapping package="cn.lonecloud.domain" >  
    <class name="Customer" table="t_customer" lazy="true">  
        <!--hibernate为我们生成主键id-->  
        <id name="id">  
            <generator class="uuid" />  
        </id>  
          
        <!--默认把类的变量映射为相同名字的表列，当然我们使用column属性修改表字段-->  
        <property name="customerName" column="customerName"></property>    
        <set name="orders" lazy="extra" fetch="join" cascade="all-delete-orphan">  <!-- lazy fetch -->
            <key column="customer_id"></key>
            <one-to-many class="cn.lonecloud.domain.Order"/>
        </set>
        
    </class>  
</hibernate-mapping>

8.Order.java

package cn.lonecloud.domain;

import java.io.Serializable;

public class Order  implements Serializable{
 
     private String id;
     
     private String orderNumber;
     
     private float price;
     
     private Customer customer;
     

    public Customer getCustomer() {
        return customer;
    }

    public void setCustomer(Customer customer) {
        this.customer = customer;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getOrderNumber() {
        return orderNumber;
    }

    public void setOrderNumber(String orderNumber) {
        this.orderNumber = orderNumber;
    }

    public float getPrice() {
        return price;
    }

    public void setPrice(float price) {
        this.price = price;
    }
     
     
     
     
     
}

9.Order.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">  
<hibernate-mapping package="cn.lonecloud.domain" >  
    <class name="Order" table="t_order" >  
        <!--hibernate为我们生成主键id-->  
        <id name="id">  
            <generator class="uuid" />  
        </id>  
          
        <!--默认把类的变量映射为相同名字的表列，当然我们使用column属性修改表字段-->  
        <property name="orderNumber" column="orderNumber"></property>    
        <property name="price" column="price"></property>    
        <many-to-one name="customer" class="cn.lonecloud.domain.Customer">
           <column name="customer_id"/>
        </many-to-one>
    </class>  
</hibernate-mapping>