Junky's IT Notebook

Eclipse下Hibernate入門

1.開發環境
???? Eclipse 3.2＋MySQL 4.0.16＋Hibernate3.0
??? 首先應該安裝好Eclipse和MySQL，此外準備好MySQL的JDBC Driver和Hibernate3.0,相關下載地址如下：
???? Eclipse SDK：
??????? http://www.eclipse.org/downloads/index.php?
?????? MySQL及MySQL的JDBC Driver:
?????????? http://www.mysql.org
?????? Hibernate:
????????? http://www.hibernate.org
?????? 此外我還安裝了Eclipse的一個Hibernate插件：
???? Hibernate synchronizer
?????????? http://hibernatesynch.sourceforge.net

?????? Plugin Search:
???????? http://eclipse-plugins.2y.net/eclipse/search.jsp?

?????? Hibernate synchronizer插件的安裝和配置有問題請直接Google。

???? 在工程中其實只用到了Hibernate synchronizer插件的一部分功能，Hibernate依賴的相關jar包最好還是手動添加，因為最開始用Hibernate synchronizer添加時總是發生錯誤。
???? 將下載的Mysql driver和Hibernate包解壓縮，我們需要的只是里面相關的jar，在Eclipse中新建Mysql_Driver和Hibernate兩個user library,將mysql-connector-java-3.0.15-ga-bin.jar加入Mysql_Driver中，將hibernate3.jar，
，log4j-1.2.11.jar，antlr-2.7.5H3.jar，asm.jar，asm-attrs.jar，cglib-2.1.2.jar，commons-collections-2.1.1.jar，commons-logging-1.0.4.jar，dom4j-1.6.1.jar，ehcache-1.1.jar，jta.jar加入到Hibernate中。

2.開始
在Mysql中新建test數據庫（Mysql其實有個空的test數據庫），然后新建下面的Table

create table user (
?id int(10) not null auto_increment primary key,
?name varchar(20) not null,
?password varchar(20) not null,
?email varchar(50),
?address varchar(100)
)type=innodb;

新建Java Project，將Mysql_Driver,Hibernate兩個user library添加到該工程的java build path中。

新建與數據表對應的POJO類：User和Contact

/**
?*
?*?
?*/
package com.user;

/**
?* @author lzy
?*
?*/
public class User{
??? private Integer id;
??? private String name;
??? private String password;
??? private Contact contact;
???

?/**
? * @return Returns the id.
? */
?public Integer getId() {
??return id;
?}
?/**
? * @param id The id to set.
? */
?public void setId(Integer id) {
??this.id = id;
?}
?/**
? * @return Returns the name.
? */
?public String getName() {
??return name;
?}
?/**
? * @param name The name to set.
? */
?public void setName(String name) {
??this.name = name;
?}
?/**
? * @return Returns the password.
? */
?public String getPassword() {
??return password;
?}
?/**
? * @param password The password to set.
? */
?public void setPassword(String password) {
??this.password = password;
?}
?/**
? * @return Returns the contact.
? */
?public Contact getContact() {
??return contact;
?}
?/**
? * @param contact The contact to set.
? */
?public void setContact(Contact contact) {
??this.contact = contact;
?}
???
???
}
/**
?*
?*/
package com.user;

/**
?* @author lzy
?*
?*/
public class Contact {
?private String email;
??? private String address;

?/**
? * @return Returns the address.
? */
?public String getAddress() {
??return address;
?}
?/**
? * @param address The address to set.
? */
?public void setAddress(String address) {
??this.address = address;
?}
?/**
? * @return Returns the email.
? */
?public String getEmail() {
??return email;
?}
?/**
? * @param email The email to set.
? */
?public void setEmail(String email) {
??this.email = email;
?}
}

之后可以用synchronizer插件生成Hibernate配置文件和映射文件（相關過程可以參考http://www.ideagrace.com/html/doc/2005/08/01/00315.html)，不過映射文件必須稍作修改。

hibernate.cfg.xml
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration
??? PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN"
??? "

<hibernate-configuration>
??? <session-factory >

??<!-- local connection properties -->
??<property name="hibernate.connection.url">jdbc:mysql://localhost/test</property>
??<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
??<property name="hibernate.connection.username"></property>
??<property name="hibernate.connection.password"></property>
??<!-- property name="hibernate.connection.pool_size"></property -->

??<!-- dialect for MySQL -->
??????? <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

??????? <property name="hibernate.show_sql">True</property>
??????? <property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>
??? ?<mapping resource="User.hbm.xml"/>

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

User.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
?"-//Hibernate/Hibernate Mapping DTD//EN"
?"

<hibernate-mapping package="com.user">
?<class
??name="User"
??table="user"
?>
??<id
???name="Id"
???type="integer"
???column="id"
??>
???<generator class="native"/>
??</id>

??<property
???name="Name"
???column="name"
???type="string"
???not-null="true"
???length="20"
??/>
??<property
???name="Password"
???column="password"
???type="string"
???not-null="true"
???length="20"
??/>
??<component name="Contact" class="Contact">
???<property
???name="Email"
???column="email"
???type="string"
???not-null="false"
???length="50"
??/>
??<property
???name="Address"
???column="address"
???type="string"
???not-null="false"
???length="100"
??/>
??</component>
??

?</class>?
</hibernate-mapping>

?

3.測試
添加一個測試類：HibernateTest

package com.user;

import java.util.List;
import java.util.ListIterator;

import org.hibernate.*;
import org.hibernate.cfg.*;

public class HibernateTest {
??? public static void main(String[] args) throws HibernateException {
??????? SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();
???????
??????? //
??????? //testInsert(sessionFactory);
???????
??????? //
??????? testQuery(sessionFactory);
???????
?????????
??????? sessionFactory.close();
???????
??? }
??? public static void testInsert( SessionFactory sessionFactory )throws HibernateException {
??? ?
? ?? ?Session session = sessionFactory.openSession();
??????? Transaction tx= session.beginTransaction();
??????? User user = new User();
??????? Contact contact=new Contact();
??????? contact.setEmail("email");
??????? contact.setAddress("address");
???????
??????? user.setName("caterpillar");
??????? user.setPassword("password");
??????? user.setContact(contact);
???????
??????? session.save(user);
??????? tx.commit();
??????? session.close();
??????? System.out.println("OK！");
? ?}
???
??? public static void testQuery( SessionFactory sessionFactory )throws HibernateException {
??? ?
??? ?Session session = sessionFactory.openSession();
??????? Transaction tx= session.beginTransaction();
??????? User user = new User();
??????? Contact contact=new Contact();
?????????????????
??????? Query query=session.createQuery("from User as user");
??????? //query.setCharacter(1, 'M');
??????? List names =query.list();
??????? for(ListIterator it=names.listIterator();it.hasNext();){
????????? ?user= (User)it.next();
????????? ?System.out.println("Id: " + user.getId());
??????????? System.out.println("name: " + user.getName());
??????????? System.out.println("password: " + user.getPassword());
??????????? if(user.getContact()!=null){
??????????? ?
??????????? ?if(user.getContact().getEmail()!=null){
??????????? ??System.out.println("Email: " + user.getContact().getEmail());
??????????? ?}
??????????? ?if(user.getContact().getAddress()!=null){
??????????? ??System.out.println("Address: " + user.getContact().getAddress());
???????????????
??????????? ?}
??????????? }
???????????
???????????
???????????
??????? }
?????????
??????
??????? tx.commit();
??????? session.close();
??? ?
??? }
}

posted on 2006-05-22 20:35 junky 閱讀(263) 評論(0)  編輯  收藏