7.优化Servlet
7.1目的
减少Servlet的数量,现在是一个功能一个Servlet,将其优化为一个模块一个Servlet,相当于在数据库中一张表对应一个Servlet,在Servlet中提供不同的方法,完成用户的请求。
Idea控制台中文乱码解决:-Dfile.encoding=gb2312
7.2BaseServlet编写
package cn.itcast.travel.web.servlet; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; public class BaseServlet extends HttpServlet { @Override protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { // System.out.println("BaseServle的service方法执行了"); //完成方法分发 //1.获取请求路径 String uri = req.getRequestURI(); ///travel/user/add // System.out.println(uri); //2.获取方法名称 String methodName = uri.substring(uri.lastIndexOf('/') + 1); // System.out.println(methodName); //add //3.获取方法对象 //this谁调用我,我代表谁 // System.out.println(this); //UserServlet对象 try { Method method = this.getClass().getMethod(methodName, HttpServletRequest.class, HttpServletResponse.class); //忽略访问权限修饰符获取方法 // Method method = this.getClass().getDeclaredMethod(methodName, HttpServletRequest.class, HttpServletResponse.class); //4.执行方法 //暴力反射 // method.setAccessible(true); method.invoke(this,req,resp); } catch (NoSuchMethodException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (InvocationTargetException e) { e.printStackTrace(); } } }
7.3UserServlet改写
package cn.itcast.travel.web.servlet; import cn.itcast.travel.domain.ResultInfo; import cn.itcast.travel.domain.User; import cn.itcast.travel.service.UserService; import cn.itcast.travel.service.impl.UserServiceImpl; import com.fasterxml.jackson.databind.ObjectMapper; import org.apache.commons.beanutils.BeanUtils; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import java.io.IOException; import java.lang.reflect.InvocationTargetException; import java.util.Map; @WebServlet("/user/*") //user/add user/find public class UserServlet extends BaseServlet { //声明一个UserService成员变量 private UserService service = new UserServiceImpl(); /* 注册功能 */ public void regist(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //验证校验 String check = request.getParameter("check"); //从sesion中获取验证码 HttpSession session = request.getSession(); String checkcode_server = (String) session.getAttribute("CHECKCODE_SERVER"); session.removeAttribute("CHECKCODE_SERVER");//为了保证验证码只能使用一次 //比较 if (checkcode_server == null || !checkcode_server.equalsIgnoreCase(check)) { //验证码错误 ResultInfo info = new ResultInfo(); //注册失败 info.setFlag(false); info.setErrorMsg("验证码错误"); //将info对象序列化为json ObjectMapper mapper = new ObjectMapper(); String json = mapper.writeValueAsString(info); response.setContentType("application/json;charset=utf-8"); response.getWriter().write(json); return; } //1.获取数据 Map<String, String[]> map = request.getParameterMap(); //2.封装对象 User user = new User(); try { BeanUtils.populate(user, map); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (InvocationTargetException e) { e.printStackTrace(); } //3.调用service完成注册 // UserService service = new UserServiceImpl(); boolean flag = service.regist(user); ResultInfo info = new ResultInfo(); //4.响应结果 if (flag) { //注册成功 info.setFlag(true); } else { //注册失败 info.setFlag(false); info.setErrorMsg("注册失败!"); } ObjectMapper mapper = new ObjectMapper(); String json = mapper.writeValueAsString(info); //将json数据写回客户端 //设置content-type response.setContentType("application/json;charset=utf-8"); response.getWriter().write(json); } /* 登录功能 */ public void login(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //1.获取用户名和密码数据 Map<String, String[]> map = request.getParameterMap(); //2.封装User对象 User user = new User(); try { BeanUtils.populate(user, map); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (InvocationTargetException e) { e.printStackTrace(); } //3.调用Service查询 // UserService service = new UserServiceImpl(); User u = service.login(user); ResultInfo info = new ResultInfo(); //4.判断用户对象是否为null if (u == null) { //用户名密码或错误 info.setFlag(false); info.setErrorMsg("用户名或密码错误"); } //5.判断用户是否激活 if (u != null && !"Y".equals(u.getStatus())) { //用户尚未激活 info.setFlag(false); info.setErrorMsg("您尚未激活,请激活"); } //6.判断登录成功 if (u != null && "Y".equals(u.getStatus())) { request.getSession().setAttribute("user", u);//登录成功标记 //登录成功 info.setFlag(true); } //响应数据 ObjectMapper mapper = new ObjectMapper(); response.setContentType("application/json;charset=utf-8"); mapper.writeValue(response.getOutputStream(), info); } /* 查询单个对象 */ public void findOne(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //从session中获取登录用户 Object user = request.getSession().getAttribute("user"); //将user写回客户端 ObjectMapper mapper = new ObjectMapper(); response.setContentType("application/json;charset=utf-8"); mapper.writeValue(response.getOutputStream(), user); } /* 退出功能 */ public void exit(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //1.销毁session request.getSession().invalidate(); //2.跳转登录页面 response.sendRedirect(request.getContextPath() + "/login.html"); } /* 激活功能 */ public void active(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //1.获取激活码 String code = request.getParameter("code"); if (code != null) { //2.调用service完成激活 // UserService service = new UserServiceImpl(); boolean flag = service.active(code); //3.判断标记 String msg = null; if (flag) { //激活成功 msg = "激活成功,请<a href='login.html'>登录</a>"; } else { //激活失败 msg = "激活失败,请联系管理员!"; } response.setContentType("text/html;charset=utf-8"); response.getWriter().write(msg); } } }
注:改写完成之后,相应的html文件中的路径也要改一下。
8.分类数据展示
8.1效果
8.2分析
8.3后台代码
CategoryServlet
package cn.itcast.travel.web.servlet; import cn.itcast.travel.domain.Category; import cn.itcast.travel.service.CategoryService; import cn.itcast.travel.service.impl.CategoryServiceImpl; import com.fasterxml.jackson.databind.ObjectMapper; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.util.List; @WebServlet("/category/*") public class CategoryServlet extends BaseServlet { private CategoryService service = new CategoryServiceImpl(); /* 查询所有 */ public void findAll(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //1.调用service查询所有 List<Category> cs = service.findAll(); //2.序列化json返回 // ObjectMapper mapper = new ObjectMapper(); // response.setContentType("application/json;charset=utf-8"); // mapper.writeValue(response.getOutputStream(),cs); writeValue(cs,response); } public void find(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("CategoryServlet的find方法..."); } }
CategoryService
package cn.itcast.travel.service; import cn.itcast.travel.domain.Category; import java.util.List; public interface CategoryService { List<Category> findAll(); }
package cn.itcast.travel.service.impl; import cn.itcast.travel.dao.CategoryDao; import cn.itcast.travel.dao.impl.CategoryDaoImpl; import cn.itcast.travel.domain.Category; import cn.itcast.travel.service.CategoryService; import java.util.List; public class CategoryServiceImpl implements CategoryService { private CategoryDao categoryDao = new CategoryDaoImpl(); @Override public List<Category> findAll() { return categoryDao.findAll(); } }
CategoryDao
package cn.itcast.travel.dao; import cn.itcast.travel.domain.Category; import java.util.List; public interface CategoryDao { List<Category> findAll(); }
package cn.itcast.travel.dao.impl; import cn.itcast.travel.dao.CategoryDao; import cn.itcast.travel.domain.Category; import cn.itcast.travel.util.JDBCUtils; import org.springframework.jdbc.core.BeanPropertyRowMapper; import org.springframework.jdbc.core.JdbcTemplate; import java.util.List; public class CategoryDaoImpl implements CategoryDao { private JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource()); @Override public List<Category> findAll() { String sql = "select * from tab_category "; return template.query(sql,new BeanPropertyRowMapper<Category>(Category.class)); } }
在BaseServlet中封装了序列化json的方法
package cn.itcast.travel.web.servlet; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.databind.ObjectMapper; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; public class BaseServlet extends HttpServlet { @Override protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { // System.out.println("BaseServle的service方法执行了"); //完成方法分发 //1.获取请求路径 String uri = req.getRequestURI(); ///travel/user/add // System.out.println(uri); //2.获取方法名称 String methodName = uri.substring(uri.lastIndexOf('/') + 1); // System.out.println(methodName); //add //3.获取方法对象 //this谁调用我,我代表谁 // System.out.println(this); //UserServlet对象 try { Method method = this.getClass().getMethod(methodName, HttpServletRequest.class, HttpServletResponse.class); //忽略访问权限修饰符获取方法 // Method method = this.getClass().getDeclaredMethod(methodName, HttpServletRequest.class, HttpServletResponse.class); //4.执行方法 //暴力反射 // method.setAccessible(true); method.invoke(this,req,resp); } catch (NoSuchMethodException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (InvocationTargetException e) { e.printStackTrace(); } } /* 直接将传入的对象序列化为json,并且写回客户端 */ public void writeValue(Object obj,HttpServletResponse response) throws IOException { ObjectMapper mapper = new ObjectMapper(); response.setContentType("application/json;charset=utf-8"); mapper.writeValue(response.getOutputStream(),obj); } /* 将传入的对象序列化返回 */ public String writeValueAsString(Object obj) throws JsonProcessingException { ObjectMapper mapper = new ObjectMapper(); return mapper.writeValueAsString(obj); } }
8.4前台代码
header.html加载后,发送ajax请求,请求category/findAll
<!-- 头部 start --> <script> $(function () { //查询用户信息 $.get("user/findOne",{},function (data) { //{uid:1,name:'李四'} var msg = "欢迎回来,"+data.name; $("#span_username").html(msg); }); //查询分类数据 $.get("category/findAll",{},function (data) { //[{cid:1,cname:国内游},{},{}] var lis = '<li class="nav-active"><a href="index.html">首页</a></li>'; //遍历数组,拼接字符串 for (var i = 0; i < data.length; i++) { var li =' <li><a href="favoriterank.html">'+data[i].cname+'</a></li>' lis += li; } //拼接收藏榜的li lis+= ' <li><a href="favoriterank.html">收藏排行榜</a></li>'; //将lis中的内容设置到ul的html中 $("#category").html(lis); }); }); </script> <!-- 头部 start --> <header id="header"> <div class="top_banner"> <img src="images/top_banner.jpg" alt=""> </div> <div class="shortcut"> <!-- 未登录状态 --> <div class="login_out"> <a href="login.html">登录</a> <a href="register.html">注册</a> </div> <!-- 登录状态 --> <div class="login"> <span id="span_username"> </span> <a href="myfavorite.html" class="collection">我的收藏</a> <a href="javascript:location.href='exitServlet';">退出</a> </div> </div> <div class="header_wrap"> <div class="topbar"> <div class="logo"> <a href="/"><img src="images/logo.jpg" alt=""></a> </div> <div class="search"> <input name="" type="text" placeholder="请输入路线名称" class="search_input" autocomplete="off"> <a href="javascript:;" class="search-button">搜索</a> </div> <div class="hottel"> <div class="hot_pic"> <img src="images/hot_tel.jpg" alt=""> </div> <div class="hot_tel"> <p class="hot_time">客服热线(9:00-6:00)</p> <p class="hot_num">400-618-9090</p> </div> </div> </div> </div> </header> <!-- 头部 end --> <!-- 首页导航 --> <div class="navitem"> <ul id="category" class="nav"> <!-- <li class="nav-active"><a href="index.html">首页</a></li> <li><a href="route_list.html">门票</a></li> <li><a href="route_list.html">酒店</a></li> <li><a href="route_list.html">香港车票</a></li> <li><a href="route_list.html">出境游</a></li> <li><a href="route_list.html">国内游</a></li> <li><a href="route_list.html">港澳游</a></li> <li><a href="route_list.html">抱团定制</a></li> <li><a href="route_list.html">全球自由行</a></li> <li><a href="favoriterank.html">收藏排行榜</a></li>--> </ul> </div>