ITEEDU

Hibernate Gossip: Map

User.java

package onlyfun.caterpillar;

import java.util.Map;

public class User {
    private Integer id;
    private String name;
    private Map items;

    // 必須要有一個預設的建構方法
    // 以使得Hibernate可以使用Constructor.newInstance()建立物件
    public User() {
    }

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Map getItems() {
        return items;
    }

    public void setItems(Map items) {
        this.items = items;
    }

    public void addItem(String name, String description) {
        items.put(name, description);
    }
    
    public void removeItem(String name) {
        items.remove(name);
    }
}

CREATE TABLE user (
    id INT(11) NOT NULL auto_increment PRIMARY KEY,
    name VARCHAR(100) NOT NULL default ''
);

CREATE TABLE item (
    id INT(11) NOT NULL,
    name VARCHAR(100) NOT NULL default '',
    description VARCHAR(100) NOT NULL default ''
);

User.hbm.xml

<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE hibernate-mapping 
    PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" 
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> 

<hibernate-mapping> 
    <class name="onlyfun.caterpillar.User" table="user"> 

        <id name="id" column="id" type="java.lang.Integer"> 
            <generator class="native"/> 
        </id> 

        <property name="name" 
                  column="name" 
                  type="java.lang.String"/> 
       
        <map name="items" table="item"> 
            <key column="id"/> 
            <index column="name" type="java.lang.String"/> 
            <element column="description" type="java.lang.String"/> 
        </map> 
        
    </class> 

</hibernate-mapping>

 User user1 = new User();
user1.setItems(new HashMap());
user1.setName("caterpillar");
user1.addItem("Book", "Java Gossip");
user1.addItem("DC", "Caxxx A80");
        
User user2 = new User();
user2.setItems(new HashMap());
user2.setName("momor");
user2.addItem("Doll", "Snoppy world");     

Session session = sessionFactory.openSession();
Transaction tx = session.beginTransaction();
session.save(user2);
tx.commit();
session.close();