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="${sessionScope.li}"> <TR> <TD class=house-thumb><span><A href="details.htm" target="_blank"><img src="images/thumb_house.gif" width="100" height="75" alt=""></a></span></TD> <TD> <DL> <!--标题，价格--> <DT><A href="houseid?id=${mind.id}" target="_blank">${mind.title}</A></DT> <TD class=house-price><SPAN>${mind.price}</SPAN>元/月</TD></TR> </c:forEach>新闻热点
疑难解答
