俗话说："好记性不如烂笔头"。本人学习Hibernate也有一个星期了，对Hibernate也有一个初步的了解。下面对Hibernate显示数据做个笔记，使用租房系统的Hibernate+jsp+selvect。
第一步：编写房屋实体类
/*
* 房屋实体类
*/ public class House {
private int id;//房屋id
private String title;//标题
private String description;//描述
private String fdate;//日期
private String price;//价格
private String contact;//面积 //省略get和set方法
}
第二步：配置House.hbm.xml映射
<?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
package="entity"> <class name="House" table="House">
<id name="id">
<generator class="increment"/>
</id> <property name="title" />
<property name="description" />
<property name="fdate" />
<property name="price" />
<property name="contact" /> </class> </hibernate-mapping>
第三步：配置hibernate.cfg.xml数据库映射（别忘了导入hibernate必备的架包）
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration>
<session-factory name="foo">
<!-- 数据库方言 -->
<property name="dialect">
org.hibernate.dialect.OracleDialect
</property>
<!-- 连接数据库Url -->
<property name="hibernate.connection.url">
jdbc:oracle:thin:@localhost:1521:orcl
</property>
<!-- 连接驱动 -->
<property name="hibernate.connection.driver_class">
oracle.jdbc.driver.OracleDriver
</property>
<!-- 用户名 -->
<property name="hibernate.connection.username">epet</property>
<!-- 密码 -->
<property name="hibernate.connection.password">123456</property> <!-- 在控制台打印sql信息 -->
<property name="show_sql">true</property>
<!-- 创建表结构 -->
<property name="hibernate.hbm2ddl.auto">update</property> <!-- 配置映射信息 --> <mapping resource="entity/House.hbm.xml" /> </session-factory>
</hibernate-configuration>
第四步：编写dao层和daoImpl层
/*
* 查询所有房屋
*/
public interface HouseDao {
/*
* 查询所有房屋
*/
public List<House> selecthouse(); }
public class HouseDaoImpl implements HouseDao{
/*
* 查询所有房屋
*
* (non-Javadoc)
* @see Dao.HouseDao#selecthouse()
*/
public List<House> selecthouse() {
// TODO Auto-generated method stub
Session session = HibernateUtil.getSession();
//查询房屋实体类
String hql="from House";
Query q=session.createQuery(hql);
List<House> list = q.list();
return list;
}
}
注意：Hibernate查询的实体，而不是数据库表
第五步：编写Selvect和web.xml配置
package selvect; import java.io.IOException;
import java.io.PrintWriter;
import java.util.List; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import entity.House; import Biz.HouseBiz;
import Biz.Impl.HouseBizImpl; public class SelectAllServlet extends HttpServlet { /**
* Destruction of the servlet. <br>
*/
public void destroy() {
System.out.println("销毁select");
} /**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request,response);
// response.setContentType("text/html");
// PrintWriter out = response.getWriter();
// out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
// out.println("<HTML>");
// out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
// out.println(" <BODY>");
// out.print(" This is ");
// out.print(this.getClass());
// out.println(", using the GET method");
// out.println(" </BODY>");
// out.println("</HTML>");
// out.flush();
// out.close();
} /**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { HouseBiz mb=new HouseBizImpl(); List<House> li=mb.selecthouse();
request.getSession().setAttribute("li", li);
response.sendRedirect("list.jsp"); //request.getRequestDispatcher("index.jsp").forward(request, response);
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
System.out.println("初始化servlet");
} }
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <!--查询房屋-->
<servlet>
<servlet-name>SelectAllServlet</servlet-name>
<servlet-class>selvect.SelectAllServlet</servlet-class>
</servlet> <!-- 映射servlet -->
<servlet-mapping>
<servlet-name>SelectAllServlet</servlet-name>
<url-pattern>/SelectAllServlet</url-pattern>
</servlet-mapping> <welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
在jsp页面显示
<LI class=bold>房屋信息</LI>
<c:forEach var="mind" items="${sessionScope.li}">
<TR>
<TD class=house-thumb><span><A href="details.htm" target="_blank"><img src="data:images/thumb_house.gif" width="100" height="75" alt=""></a></span></TD>
<TD> <DL>
<!--标题，价格-->
<DT><A href="houseid?id=${mind.id}" target="_blank">${mind.title}</A></DT> <TD class=house-price><SPAN>${mind.price}</SPAN>元/月</TD></TR> </c:forEach>