hibernate3.2上使用UserType范例

仔细看看hibernate的DOC发现不少惊奇的东东,后悔自己的旁门助道是多么的无用.
本次主要实现目的.
数据库表:EchoMessageEmail,其中有三个字段id(自动编号)\name\Email(varchar)
实现目的:数据库字段中Email的值是类似于heweiya@gmail.com;heweiya@21cn.com;www.1718zx.cn的.所以要求以List表达.
也就是生成的DataModel当中是有一个List对象的.
.hbm.xml

xml 代码

<?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="com.travelsky.hibernate.po.EchoMessageEmail" table="echo_message_email">
<id name="id" type="java.lang.Integer">
<column name="ID" />
<generator class="native"></generator>
</id>
<property name="name" type="java.lang.String">
<column name="NAME" length="50" not-null="true" />
</property>
<property name="email" type="com.travelsky.hibernate.po.EmailList" lazy="true">
<column name="EMAIL"/>
</property>
</class>
</hibernate-mapping>
对应的POJO:

java 代码

package com.travelsky.hibernate.po;
import java.util.List;

/**
* EchoMessageEmail generated by MyEclipse Persistence Tools
*/

public class EchoMessageEmail implements java.io.Serializable {

private Integer id;
private String name;
private List email;

/** default constructor */
public EchoMessageEmail() {
}

/** minimal constructor */
public EchoMessageEmail(String name) {
this.name = name;
}

/** full constructor */
public EchoMessageEmail(String name, List email) {
this.name = name;
this.email = email;
}

// 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 List getEmail() {
return email;
}

public void setEmail(List email) {
this.email = email;
}

}
其中的UserType的一个类:EmailList

java 代码

package com.travelsky.hibernate.po;

import java.io.Serializable;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;
import java.util.ArrayList;
import java.util.List;

import org.apache.commons.lang.StringUtils;
import org.hibernate.HibernateException;
import org.hibernate.Hibernate;

/**
* 必须得引用java.io.Serializable,UserType是反序列化
* 另外，我使用的hibernate版本是3.2，UserType从2.0到3.2有很大的差异，应该多多看看官方的doc
*
* @author @家军.严重注意org.hibernate.usertype.UserType,不要自己造车呀.
*
*/
public class EmailList implements java.io.Serializable,org.hibernate.usertype.UserType{

private List emails;

private static final String SPLITTER = ";";

private static final int[] TYPES = new int[] { Types.VARCHAR };

public int[] sqlTypes() {

return TYPES;
}

public Class returnedClass() {
// TODO Auto-generated method stub
return List.class;
}

public boolean equals(Object x, Object y) throws HibernateException {
if (x == y)
return true;
if (x != null && y != null) {
List xList = (List) x;
List yList = (List) y;
if (xList.size() != yList.size())
return false;
for (int i = 0; i < xList.size(); i++) {
String str1 = (String) xList.get(i);
String str2 = (String) yList.get(i);
if (!str1.equals(str2))
return false;
}
return true;
}
return false;
}

public Object nullSafeGet(ResultSet rs, String[] names, Object owner)
throws HibernateException, SQLException {
String value = (String) Hibernate.STRING.nullSafeGet(rs, names[0]);
if (value != null) {
return parse(value);
} else {
return null;
}
}

public void nullSafeSet(PreparedStatement st, Object value, int index)
throws HibernateException, SQLException {
System.out.println("Set method excecuted");
if (value != null) {
String str = assemble((List) value);
Hibernate.STRING.nullSafeSet(st, str, index);
} else {
Hibernate.STRING.nullSafeSet(st, value, index);
}

}

public Object deepCopy(Object value) throws HibernateException {
List sourcelist = (List) value;
List targetlist = new ArrayList();
targetlist.addAll(sourcelist);
return targetlist;
}

public boolean isMutable() {
return false;
}

private String assemble(List emailList) {
StringBuffer strBuf = new StringBuffer();
for (int i = 0; i < emailList.size() - 1; i++) {
strBuf.append(emailList.get(i)).append(SPLITTER);
}
strBuf.append(emailList.get(emailList.size() - 1));
return strBuf.toString();
}

private List parse(String value) {
String[] strs = StringUtils.split(value, SPLITTER);
List emailList = new ArrayList();
for (int i = 0; i < strs.length; i++) {
emailList.add(strs[i]);
}
return emailList;
}

public Object assemble(Serializable arg0, Object arg1) throws HibernateException {
// TODO Auto-generated method stub
return null;
}

public Serializable disassemble(Object arg0) throws HibernateException {
// TODO Auto-generated method stub
return null;
}

public int hashCode(Object arg0) throws HibernateException {
// TODO Auto-generated method stub
return 0;
}

public Object replace(Object arg0, Object arg1, Object arg2) throws HibernateException {
// TODO Auto-generated method stub
return null;
}

}
测试类:

java 代码

package com.travelsky.test;
import java.util.List;
import java.util.ListIterator;
import com.travelsky.hibernate.po.EchoMessageEmail;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

public class HibernateTest {

public static void main(String[] args) throws Exception{
Configuration config = new Configuration().configure();
SessionFactory factory = config.buildSessionFactory();
Session session = factory.openSession();
Query query = session.createQuery("from EchoMessageEmail as a");
/**
* 理论上来说,这里不存在lazy加载,为了安全起见使用了Iterator
*
*/
ListIterator iterator = query.list().listIterator();
EchoMessageEmail tt = (EchoMessageEmail) iterator.next();//只找第一个
List emails = tt.getEmail();
for (int i = 0; i < emails.size(); i++) {
String emailStr = (String)emails.get(i);
System.out.println(emailStr);
}
session.close();
}
}

Java代码