首选说下我们开发准备吧!
开发环境:Tomcat 6.0JDK1.6MySQL5.0
开发工具:Eclipse-jee(Eclipse官网上下载)
所要下载框架包:struts-2.0.11.2-all.zipspring-framework-2.5.5-with-dependencies.ziphibernate-distribution-3.3.1.GA-dist.zip这 3个压缩包在其官方网站WebSite都可以下载当然这个小项目所要用到不止这些我们用到时候再去下载
好我们来开始第阶段探索——Hibernate3.3Annotation实现
新建我们Dynamic Web Project取名为"ssh_annotation”配置Tomcat6.0支持打开MySQL建立个空数据库取名为"ssh_annotation"记得要引进MySQLJDBC驱动包mysql-connector-java-5.0.8-bin.jar
在解压缩hibernate-distribution-3.3.1.GA目录中把hibernate.jar和librequired下所用jar包引进到我们项目lib目录下
不知道用过Hibernate3.3开发朋友会不会遇到过这样问题:把上面包都准备好开发Hibernate测试类时会报Caused by: java.lang.NoClassDefFoundError: org/slf4j/impl/StaticLoggerBinder 或者Caused by: java.lang.NoClassDefFoundError: org/apache/log4j/LogManager这是Hibernate3.3提供jar包缺少了slf4j-log4j12.jar这个包解决办法是:在Hibernate官方网站WebSite上下载hibernate-annotations-3.4.0.GA.zip解压缩把其lib下slf4j-log4j12.jar引进我们项目lib目录下而我们引进这个jar包后若我们没有引进log4j.jar话就会报java.lang.NoClassDefFoundError: org/apache/log4j/LogManager可能是slf4j-log4j12.jar要用log4j类吧我们也引进log4j.jar即行
当然hibernate-annotations-3.4.0.GA.zip 是我们开发Hibernate Annotation所要用到除以上面那些jar包外我们还要引进其hibernate-annotations.jar及其lib下hibernate-commons-annotations.jarejb3-persistence.jar好暂时就这些我们接下来需要用到哪些jar包时再引进
好第步来开发我们实体类User代码如下:
package com.rong.entity;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name="tb_user")
public User {
@Id @GeneratedValue(strategy=GenerationType.IDENTITY)
private id;
@Column(name="username", length=15)
private String username;
@Column(name="password", length=15)
private String password;
public getId {
id;
}
public void Id( id) {
this.id = id;
}
public String getUsername {
username;
}
public void Username(String username) {
this.username = username;
}
public String getPassword {
password;
}
public void Password(String password) {
this.password = password;
}
}
简单解释下吧:
@Entity定义User类为实体类@Id定义该属性对应列为主键@GeneratedValue(strategy=GenerationType.IDENTITY)定义主键生成策略为Indentity适用于MySQL和MS SQL等数据库@Column(name="username", length=15)定义列名和取值长度
应该不难更多有关Hibernate注解请下载并参考我整理Hibernate Annotation帮助文档 /Files/rongxh7/hibernateAannotations.rar 慢慢学吧!
当然必要XML配置文件还是要有:
<?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">
<hibernate-configuration>
<session-factory>
<!-- Database connection tings -->
<property name="connection.driver_">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost:3306/ssh_annotation</property>
<property name="connection.username">root</property>
<property name="connection.password">root</property>
<!-- 数据库言 -->
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- 将Session扔到线程里去处理 -->
<property name="current_session_context_">thread</property>
<!-- 在控制台打印SQL语句 -->
<property name="show_sql">true</property>
<!-- 自动把实体类和属性映射成数据库中表和列 -->
<property name="hbm2ddl.auto">update</property>
<!--
<mapping resource="com/rong/entity/User.hbm.xml"/>
-->
<!-- 在Hibernate中注册User实体类,区别于上面注释掉resource写法 -->
<mapping ="com.rong.entity.User"/>
</session-factory>
</hibernate-configuration>
到这里我们可以运行TomcatHibernate会根据hbm2ddl.auto自动地把实体类和属性转变成数据库中表和列但这步要事先在数据库中建立个名为"ssh_annotation"空数据库好了看下你数据库中是否有"tb_user"表生成了?!
接下来我们来开发个包装器类取名HibernateUtil代码如下:
package test.rong.hibernate;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
public HibernateUtil {
private final SessionFactory sessionFactory;
{
try {
//用xxx.hbm.xml形式配置实体映射
//sessionFactory = Configuration.configure.buildSessionFactory;
//用Annotation形式配置实体映射
sessionFactory = AnnotationConfiguration.configure.buildSessionFactory;
} catch (Throwable ex) {
.err.prln("Initial SessionFactory creation failed." + ex);
throw ExceptionInInitializerError(ex);
}
}
public SessionFactory getSessionFactory {
sessionFactory;
}
}
学过Hibernate朋友们应该对这个类不陌生吧在此我就不多解释啦注意下我注释地方就行下面我们来进行测试下载最新版本Junit4.5.jar试下感觉如何当然旧版本应该也没问题啦!写测试代码如下:
package test.rong.hibernate;
import java.util.Iterator;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.junit.Before;
import org.junit.Test;
import com.rong.entity.User;
public EntityTest {
private Session session;
@Before
public void initSession{
this.session = HibernateUtil.getSessionFactory.getCurrentSession;
}
@Test //测试添加用户
public void testSave{
session.beginTransaction;
User user = User;
user.Username("rongxh7");
user.Password("blogjava");
session.save(user);
session.getTransaction.commit;
}
@Test //测试查询用户列表
@SuppressWarnings("unchecked")
public void testQuery{
session.beginTransaction;
Query query = session.createQuery("from User u");
List<User> users = query.list;
for(Iterator<User> it = users.iterator ; it.hasNext ; ){
User user = it.next;
.out.prln("username = " + user.getUsername);
}
session.beginTransaction.commit;
}
@Test //测试查询单个用户
public void testGet{
session.beginTransaction;
User user = (User)session.get(User., 1);
.out.prln("username = " + user.getUsername);
session.getTransaction.commit;
}
@Test //测试查询修改用户
public void testUpdate{
session.beginTransaction;
User user = (User)session.load(User., 1);
user.Password("hello blogjava");
session.update(user);
session.getTransaction.commit;
}
@Test //测试删除用户
public void testDelete{
session.beginTransaction;
session.delete(session.load(User., 1));
session.getTransaction.commit;
}
}
到此我们Hibernate Annotation开发完成了你成功了没?如果有什么问题请回复我尽力为你解答!好第阶段暂告段落不要忘记我们是要做是基于AnnotatiolnSSH整合开发让我们起期待下阶段吧!
(*^-^*) 本文原创转载请注明出处 http://www.blogjava.net/rongxh7谢谢! (*^-^*)
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