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中文：

下载：hibernate annotation 3.4.0 GA

得到：hibernate-annotations.jar

　　　hibernate-commons-annotation.jar

　　　ejb3-persistence.jar

数据库：mysql

category表：id，name，description       <Pk>id

product表：id,name ,price, description ,category_id                  <pk>id  <fk>category_id

新建java project项目：

Add Hibernate Capabilities

hibernate.cfg.xml

代码；

<?xml version='1.0' encoding='UTF-8'?>

<!DOCTYPE hibernate-configuration PUBLIC

          "-//Hibernate/Hibernate Configuration DTD 3.0//EN"

          "">

<!-- Generated by MyEclipse Hibernate Tools.                   -->

<hibernate-configuration>

 <session-factory>

  <property name="dialect">

   org.hibernate.dialect.MySQLDialect

  </property>

  <property name="connection.url">

   jdbc:mysql://localhost:3307/users

  </property>

  <property name="connection.username">root</property>

  <property name="connection.password">root</property>

  <property name="connection.driver_class">

   com.mysql.jdbc.Driver

  </property>

  <property name="myeclipse.connection.profile">

   mysqlusers

  </property>

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

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

  <property name="current_session_context_class">thread</property>

  <mapping class="com.b510.examples.Product" />

  <mapping class="com.b510.examples.Category" />

 </session-factory>

</hibernate-configuration>

利用Hibernate的逆向工程生成：

Category.java      and           Product.java   

Category.java

package com.b510.examples;

import java.util.HashSet;

import java.util.Set;

// 标准注解

import javax.persistence.CascadeType;

import javax.persistence.Column;

import javax.persistence.Entity;

import javax.persistence.FetchType;

import javax.persistence.GeneratedValue;

import javax.persistence.Id;

import javax.persistence.OneToMany;

import javax.persistence.Table;

//增加的注解

import org.hibernate.annotations.GenericGenerator;

//当前的类是一个持久化类，是Category这个类。他映射了一个表category。所对应的 数据库是users

//这句：@Table(name = "category", catalog = "users")  可以省略

@Entity

@Table(name = "category", catalog = "users")

public class Category implements java.io.Serializable {

 private static final long serialVersionUID = 3240281547213597385L;

 private Integer id;

 private String name;

 private String description;

 private Set<Product> products = new HashSet<Product>(0);

 

 public Category() {

 }

 public Category(String name, String description, Set<Product> products) {

  this.name = name;

  this.description = description;

  this.products = products;

 }

 // 主键 ：@Id    主键生成方式：strategy = "increment"

 //映射表中id这个字段，不能为空，并且是唯一的

 @GenericGenerator(name = "generator", strategy = "increment")

 @Id

 @GeneratedValue(generator = "generator")

 @Column(name = "id", unique = true, nullable = false)

 public Integer getId() {

  return this.id;

 }

 public void setId(Integer id) {

  this.id = id;

 }

 //映射表中name这个字段 ，长度是500

 @Column(name = "name", length = 500)

 public String getName() {

  return this.name;

 }

 public void setName(String name) {

  this.name = name;

 }

 

 //映射表中description这个字段 ，长度是500

 @Column(name = "description", length = 500)

 public String getDescription() {

  return this.description;

 }

 public void setDescription(String description) {

  this.description = description;

 }

 //级联操作：cascade = CascadeType.ALL

 //延迟加载：fetch = FetchType.LAZY

 //映射：mappedBy = "category"

 //一对多方式

 @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "category")

 public Set<Product> getProducts() {

  return this.products;

 }

 public void setProducts(Set<Product> products) {

  this.products = products;

 }

}

Product.java

代码：

package com.b510.examples;

import javax.persistence.Column;

import javax.persistence.Entity;

import javax.persistence.FetchType;

import javax.persistence.GeneratedValue;

import javax.persistence.Id;

import javax.persistence.JoinColumn;

import javax.persistence.ManyToOne;

import javax.persistence.Table;

import org.hibernate.annotations.GenericGenerator;

@Entity

@Table(name = "product", catalog = "users")

public class Product implements java.io.Serializable {

 private static final long serialVersionUID = -1546206493725028472L;

 private Integer id;

 private Category category;

 private String name;

 private String price;

 private String descripton;

 

 public Product() {

 }

 public Product(Category category, String name, String price,

   String descripton) {

  this.category = category;

  this.name = name;

  this.price = price;

  this.descripton = descripton;

 }

 

 @GenericGenerator(name = "generator", strategy = "increment")

 @Id

 @GeneratedValue(generator = "generator")

 @Column(name = "id", unique = true, nullable = false)

 public Integer getId() {

  return this.id;

 }

 public void setId(Integer id) {

  this.id = id;

 }

 //延迟加载：多对一方式

 //关联信息：外键name = "category_id"

 @ManyToOne(fetch = FetchType.LAZY)

 @JoinColumn(name = "category_id")

 public Category getCategory() {

  return this.category;

 }

 public void setCategory(Category category) {

  this.category = category;

 }

 @Column(name = "name", length = 500)

 public String getName() {

  return this.name;

 }

 public void setName(String name) {

  this.name = name;

 }

 @Column(name = "price", length = 10)

 public String getPrice() {

  return this.price;

 }

 public void setPrice(String price) {

  this.price = price;

 }

 @Column(name = "descripton", length = 500)

 public String getDescripton() {

  return this.descripton;

 }

 public void setDescripton(String descripton) {

  this.descripton = descripton;

 }

}

测试代码：

HibernateTest.java

代码：

/**

 *

 */

package com.b510.examples;

import java.util.Set;

import org.hibernate.Session;

import org.hibernate.SessionFactory;

import org.hibernate.cfg.AnnotationConfiguration;

import org.hibernate.cfg.Configuration;

/**

 *

 * @author XHW

 *

 * @date 2011-7-20

 *

 */

public class HibernateTest {

 public static void main(String[] args) {

  HibernateTest test=new HibernateTest();

  test.add();

  test.find();

 }

 public void add(){

 Configuration config=new AnnotationConfiguration();

 config.configure();

 SessionFactory sessionFactory=config.buildSessionFactory();

 Session session=sessionFactory.getCurrentSession();

 session.beginTransaction();

 Category c=(Category)session.get(Category.class, 5);

 

 Product p=new Product();

 p.setName("计算机科学与技术");

 p.setPrice("123");

 p.setDescripton("计算机科学与技术,好啊，真是红啊");

 

 p.setCategory(c);

 c.getProducts().add(p);

 

 session.save(p);

 session.getTransaction().commit();

 }

 

 

 public void find(){

  Configuration config=new AnnotationConfiguration();

  config.configure();

  SessionFactory sessionFactory=config.buildSessionFactory();

  Session session=sessionFactory.getCurrentSession();

  session.beginTransaction();

  Category c=(Category)session.get(Category.class, 5);

   System.out.println("id: "+c.getId()+"  name:"+c.getName());

   Set<Product> p=c.getProducts();

   for(Product product:p){

    System.out.println("id:"+product.getId()+"  name:"+product.getName()+"  description:"+product.getDescripton());

   }

   session.getTransaction().commit();

 }

}

运行效果：

log4j:WARN No appenders could be found for logger (org.hibernate.cfg.annotations.Version).

log4j:WARN Please initialize the log4j system properly.

Hibernate:

    select

        category0_.id as id1_0_,

        category0_.description as descript2_1_0_,

        category0_.name as name1_0_

    from

        users.category category0_

    where

        category0_.id=?

Hibernate:

    select

        products0_.category_id as category5_1_,

        products0_.id as id1_,

        products0_.id as id0_0_,

        products0_.category_id as category5_0_0_,

        products0_.descripton as descripton0_0_,

        products0_.name as name0_0_,

        products0_.price as price0_0_

    from

        users.product products0_

    where

        products0_.category_id=?

Hibernate:

    select

        max(id)

    from

        product

Hibernate:

    insert

    into

        users.product

        (category_id, descripton, name, price, id)

    values

        (?, ?, ?, ?, ?)

Hibernate:

    select

        category0_.id as id5_0_,

        category0_.description as descript2_5_0_,

        category0_.name as name5_0_

    from

        users.category category0_

    where

        category0_.id=?

id: 5  name:xml33

Hibernate:

    select

        products0_.category_id as category5_1_,

        products0_.id as id1_,

        products0_.id as id4_0_,

        products0_.category_id as category5_4_0_,

        products0_.descripton as descripton4_0_,

        products0_.name as name4_0_,

        products0_.price as price4_0_

    from

        users.product products0_

    where

        products0_.category_id=?

id:9  name:计算机科学与技术  description:计算机科学与技术,好啊，真是红啊