Hibernate Annotation外部キーに基づく一方向多対一関連付け
10370 ワード
実は一対多と多対一は同じで、ただ問題を見る角度が違うだけです.
必要な注釈ラベルは前の文章を参考にしてください.それらのラベルは私が前のプロジェクトからまとめたものです.
SQLスクリプト:
//Category.java
//Product.java
//HibernateUti.java
//Hibernate.cfg.xml
この例を通して,プライマリキー生成方式パラメータの設定も発見したが,ほほほ.
必要な注釈ラベルは前の文章を参考にしてください.それらのラベルは私が前のプロジェクトからまとめたものです.
SQLスクリプト:
-- MySQL dump 10.13 Distrib 5.1.55, for Win32 (ia32)
--
-- Host: localhost Database: hibernate_demo
-- ------------------------------------------------------
-- Server version 5.1.55-community
/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8 */;
/*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */;
/*!40103 SET TIME_ZONE='+00:00' */;
/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;
--
-- Table structure for table `category`
--
DROP TABLE IF EXISTS `category`;
/*!40101 SET @saved_cs_client = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `category` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(30) NOT NULL,
`description` varchar(30) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=2 DEFAULT CHARSET=utf-8;
/*!40101 SET character_set_client = @saved_cs_client */;
--
-- Dumping data for table `category`
--
LOCK TABLES `category` WRITE;
/*!40000 ALTER TABLE `category` DISABLE KEYS */;
INSERT INTO `category` VALUES (1,'fruit','fruit category');
/*!40000 ALTER TABLE `category` ENABLE KEYS */;
UNLOCK TABLES;
--
-- Table structure for table `product`
--
DROP TABLE IF EXISTS `product`;
/*!40101 SET @saved_cs_client = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `product` (
`id` int(11) NOT NULL,
`name` varchar(30) NOT NULL,
`price` int(11) NOT NULL,
`description` varchar(30) NOT NULL,
`category_id` int(11) NOT NULL,
PRIMARY KEY (`id`),
KEY `product_fk` (`category_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;
--
-- Dumping data for table `product`
--
LOCK TABLES `product` WRITE;
/*!40000 ALTER TABLE `product` DISABLE KEYS */;
INSERT INTO `product` VALUES (1,'apple',10,'apple',1);
/*!40000 ALTER TABLE `product` ENABLE KEYS */;
UNLOCK TABLES;
/*!40103 SET TIME_ZONE=@OLD_TIME_ZONE */;
/*!40101 SET SQL_MODE=@OLD_SQL_MODE */;
/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;
/*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;
/*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;
-- Dump completed on 2012-08-08 22:34:53
//Category.java
package com.zyp.examples;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import org.hibernate.annotations.GenericGenerator;
/**
* Category entity. @author MyEclipse Persistence Tools
*/
@Entity
@Table(name="category")
public class Category implements java.io.Serializable {
// Fields
private static final long serialVersionUID = 3763960444574701564L;
@Id
@GenericGenerator(name="incrementGenerator", strategy="increment")
@GeneratedValue(generator="incrementGenerator", strategy=GenerationType.IDENTITY)
@Column(name="id")
private Integer id;
@Column(name="name",nullable=false, insertable=true)
private String name;
@Column(name="description", nullable=false, insertable=true)
private String description;
// Constructors
/** default constructor */
public Category() {
}
/** full constructor */
public Category(String name, String description) {
this.name = name;
this.description = description;
}
// Property accessors
public Integer getId() {
return this.id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public String getDescription() {
return this.description;
}
public void setDescription(String description) {
this.description = description;
}
}
//Product.java
package com.zyp.examples;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
import org.hibernate.annotations.GenericGenerator;
/**
* Product entity. @author MyEclipse Persistence Tools
*/
@Entity
@Table(name="product")
public class Product implements java.io.Serializable {
// Fields
private static final long serialVersionUID = -485648626582047874L;
@Id
@GenericGenerator(name="incrementGenerator", strategy="increment")
@GeneratedValue(generator="incrementGenerator", strategy=GenerationType.IDENTITY)
@Column(name="id")
private Integer id;
@Column(name="name")
private String name;
@Column(name="price")
private Integer price;
@Column(name="description")
private String description;
@ManyToOne(targetEntity=Category.class, fetch=FetchType.LAZY, cascade={CascadeType.ALL})
@JoinColumn(name="category_id")
private Category category;
// Constructors
/** default constructor */
public Product() {
}
// Property accessors
public Integer getId() {
return this.id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public Integer getPrice() {
return this.price;
}
public void setPrice(Integer price) {
this.price = price;
}
public String getDescription() {
return this.description;
}
public void setDescription(String description) {
this.description = description;
}
public Category getCategory() {
return category;
}
public void setCategory(Category category) {
this.category = category;
}
}
//HibernateUti.java
package com.zyp.examples;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration;
public class HibernateUtil {
private static SessionFactory sessionFactory;
static {
try {
sessionFactory = new AnnotationConfiguration().configure()
.buildSessionFactory();
} catch (Throwable ex) {
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
public static void shutdown() {
getSessionFactory().close();
}
}
//Hibernate.cfg.xml
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<!-- Generated by MyEclipse Hibernate Tools. -->
<hibernate-configuration>
<session-factory>
<property name="dialect">
org.hibernate.dialect.MySQLDialect
</property>
<property name="connection.url">
jdbc:mysql://localhost:3306/hibernate_demo
</property>
<property name="connection.username">root</property>
<property name="connection.password">123</property>
<property name="connection.driver_class">
com.mysql.jdbc.Driver
</property>
<property name="myeclipse.connection.profile">mysql</property>
<property name="show_sql">true</property>
<property name="format_sql">true</property>
<mapping class="com.zyp.examples.Category" />
<mapping class="com.zyp.examples.Product" />
</session-factory>
</hibernate-configuration>
この例を通して,プライマリキー生成方式パラメータの設定も発見したが,ほほほ.
@Id
@GenericGenerator(name="incrementGenerator( )", strategy="increment( )")
@GeneratedValue(generator="incrementGenerator( )", strategy=GenerationType.IDENTITY( ))
@Column(name="id")
private Integer id;