Es wird empfohlen, einen Blick auf das von Lone Ao Canglang geschriebene Servlet+JSP+JavaBean-Entwicklungsmodell () zu werfen.
Am besten liest man sein gesamtes JavaWeb Lernzusammenfassung, es wird sehr interessant sein. Was für ein großer Gewinn! Ich habe auch gelernt, wie man JSP-Lieferparameter in eine Methode kapselt.
Ich denke, das ist besonders nützlich besonders in Sie können viel Code sparen, wenn Sie Projekte durchführen
1: Erforderliche Pakete
Basierend auf dem Inhalt des vorherigen Artikels JDBC+Servlet+jsp() wird neuer Funktionscode hinzugefügt.
Wie folgt Anzeige:
1: Code schreiben 1.zhu.jdbc.unit Erstellen Sie eine Klasse WebUtils.java unter dem Paket (Klasse zum Speichern von Parameterdefinitionen)
1 package zhu.jdbc.unit; 2 3 import java.util.Enumeration; 4 import java.util.UUID; 5 6 import javax.servlet.http.HttpServletRequest; 7 8 import org.apache.commons.beanutils.BeanUtils; 9 10 /**11 * 把request对象中的请求参数封装到bean中12 *
13 * @author Xiao_Zhu14 *
15 */16 public class WebUtils {17 18 /**19 * 将request对象转换成T对象20 *
21 * @param request22 * @param clazz23 * @return24 */25 public static <T> T request2Bean(HttpServletRequest request, Class<T> clazz) {26 /*27 * JDK中，普通的Class.newInstance()方法的定义返回Object，要将该返回类型强制转换为另一种类型;28 * 但是使用泛型的Class<T>，Class.newInstance()方法具有一个特定的返回类型;29 * java反射就是从Class<T>类开始的,Class<T>是没有公共的构造方法,虽然没有构造方法,但是有相应的方法可以获取类的变量和类型30 * “?”是一个匹配字符，匹配任意类型；“T”匹配的是某一具体的类型，如String。如果知道Class的具体类型，可以直接使用Class<T>,32 * 如Class<String>33 */34 try {// 创建对象(这里的是创建Tb_User的对象)35 T bean = clazz.newInstance();36 // 使用枚举获取 参数-->key-value 键值对37 Enumeration<String> e = request.getParameterNames();38 while (e.hasMoreElements()) {39 String key = (String) e.nextElement();40 String value = request.getParameter(key);41 BeanUtils.setProperty(bean, key, value);42 }43 return bean;44 } catch (Exception e) {45 throw new RuntimeException(e);46 }47 }48 49 /**50 * 生成UUID51 *
52 * @return53 */54 public static String makeId() {55 return UUID.randomUUID().toString();56 }57 }Servlet_TbUser2.java-Klasse (eine Klasse zum Speichern von Parameterdefinitionen)
Servlet_TbUser2 Der Code lautet wie folgt:
1 package zhu.jdbc.servlet; 2 3 import java.io.IOException; 4 import java.sql.Date; 5 import java.text.ParseException; 6 import java.text.SimpleDateFormat; 7 import java.util.List; 8 9 import javax.servlet.ServletException;10 import javax.servlet.http.HttpServlet;11 import javax.servlet.http.HttpServletRequest;12 import javax.servlet.http.HttpServletResponse;13 14 15 16 import zhu.jdbc.domain.Tb_User;17 import zhu.jdbc.service.ITb_UserService;18 import zhu.jdbc.service.imp.ITb_UserServiceImpI;19 import zhu.jdbc.unit.WebUtils;20 21 public class Servlet_TbUser2 extends HttpServlet {22 /**23 *
24 */25 private static final long serialVersionUID = 1L;26 ITb_UserService myITb_UserService = new ITb_UserServiceImpI();27 28 @Override29 protected void doGet(HttpServletRequest req, HttpServletResponse resp)30 throws ServletException, IOException {31 doPost(req, resp);32 }33 34 @Override35 protected void doPost(HttpServletRequest request,36 HttpServletResponse response) throws ServletException, IOException {37 request.setCharacterEncoding("UTF-8");// 解决乱码38 String type = request.getParameter("who");39 // 新增40 if ("Insert".equals(type)) {41 Insert(request, response);42 }43 //查询所有数据44 else if("queryAll".equals(type)){45 queryAll(request, response);46 }
47 }48 49 // 新增50 public void Insert(HttpServletRequest request, HttpServletResponse response)51 throws ServletException, IOException {52 /*注册字符串到日期的转换器
53 * ConvertUtils.register(new DateLocaleConverter(), java.util.Date.class);
54 * */ 55 //将jsp页面专递参数封装到 domain层的 Tb_User对象中56 Tb_User tb_User=WebUtils.request2Bean(request, Tb_User.class);
57 System.out.println(tb_User.getName());
58 // 把获取到的这些值放到user里59 Tb_User user = new Tb_User();60 try {61 // 下面两句是把 string 转换为 sql类型的 时间格式62 SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");63 String time=sdf.format(tb_User.getBirthday());64 user.setBirthday(new Date(sdf.parse(time).getTime()));65 user.setEmail(tb_User.getEmail());66 user.setName(tb_User.getName());67 user.setPassword(tb_User.getPassword());
68 user.setSex(tb_User.isSex());69 // 最后调用服务来添加70 String message = null;71 if (myITb_UserService.insertData(user) == true) {72 queryAll(request, response);73 } else {74 message = "新增失败!!!";75 request.setAttribute("msg", message);76 request.getRequestDispatcher("/index.jsp").forward(request, response);77 }78 } catch (Exception e1) {79 e1.printStackTrace();80 }81 }82 //查询所有的数据83 public void queryAll(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException{84 List<Tb_User> lis=myITb_UserService.queryAllData();
85 request.setAttribute("list", lis);86 request.getRequestDispatcher("/jsp/WebUtils_User.jsp").forward(request, response);87 }88 89 }WebUtils_User.jsp
1 <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> 2 <% 3 String path = request.getContextPath(); 4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; 5 %> 6 <!-- c标签要使用,那么就必须要有它 --> 7 <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%> 8 <c:set scope="page" var="url" 9 value="${pageContext.request.contextPath }"></c:set>10 11 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">12 <html>13 <head>14 <base href="<%=basePath%>"> 15 <title>My JSP 'WebUtils_User.jsp' starting page</title> 16 </head>17 18 <body>19 <div align="center"20 style="width: 400px; position: relative;left:450px">21 <form action="${url}/zhu/Servlet_TbUser2?who=Insert" method="post">22 <h4>新增用户</h4>23 姓名: <input type="text" name="name"><br />24 密码: <input type="text" name="password"><br /> 25 出生日期 : <input type="text" name="birthday"><br /> 26 性别: <select name="sex">27 <option value="0">男</option>28 <option value="1">女</option>29 </select><br /> 30 <input type="submit" value="新增"/>31 <hr />32 </form>33 </div> 34 <div align="center"style="width: 400px; position: relative;left:450px;">35 <form action="${url}/zhu/Servlet_TbUser2?who=queryAll" method="post"> 36 <input type="submit" value="查询所有的数据"/> <br/>37 <table border="1" cellspacing="0"> 38 <thead>39 <tr><td>ID</td><td>姓名</td><td>密码</td><td>日期</td><td>性别</td><td>操作</td></tr>40 </thead>41 <tbody>42 <c:forEach items="${list}" var="list">43 <tr>44 <td>${list.id }</td>45 <td>${list.name }</td>46 <td>${list.password }</td>47 <td>${list.birthday }</td> 48 <td><c:if test="${list.sex==false }">男</c:if>49 <c:if test="${list.sex==true }">女</c:if></td>50 <td><a href= "${url}/zhu/Servlet_TbUser?who=queryById&id=${list.id}" style='text-decoration:none' >修改 </a> 51 <a href= "${url}/zhu/Servlet_TbUser?who=delete&id=${list.id}" style='text-decoration:none' >删除</a> </td> 52 </tr>53 </c:forEach>54 </tbody>55 </table>56 <hr />57 </form>58 </div> 59 </body>60 </html>
Wenden Sie die Datei von jquery an -2.1.4.min.js
Wenden Sie die Datei jQuery-2.1.4.min.js in WebUtils_User.jsp an, die gerade verwendet werden kann Der vollständige Code von WebUtils_User.jsp lautet wie folgt: 
Servlet_TbUser2 vollständiger
-Code lautet wie folgt: 1 <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> 2 <% 3 String path = request.getContextPath(); 4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; 5 %> 6 <!-- c标签要使用,那么就必须要有它 --> 7 <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%> 8 <c:set scope="page" var="url" 9 value="${pageContext.request.contextPath }"></c:set>10 11 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">12 <html>13 <head>14 <base href="<%=basePath%>"> 15 <title>My JSP 'WebUtils_User.jsp' starting page</title> 16 <script type="text/javascript" src="${url}/js/jquery-2.1.4.min.js?1.1.11"></script>17 <script type="text/javascript">18 function funInsert(){19 //专递的参数和定义的变量必须要遵循驼峰形式的格式20 var userName=$("#name").val();21 var userPassword=$("#password").val();22 var userSex=$("#sex").val();23 var userBirthday=$("#birthday").val();
24 //那面的专递的参数 如:name,password...必须要与domain层的表的名称对应,25 $.post("${url}/zhu/Servlet_TbUser2",{who:'jQueryInsert',name:userName,password:userPassword,sex:userSex,birthday:userBirthday},
26 function(getData){27 console.log(getData);
28 alert(getData.msg);
29 30 },"json");31 }32 33 </script>34 </head>35 36 <body>37 38 <div align="center"39 style="width: 400px; position: relative;left:450px">40 <form action="${url}/zhu/Servlet_TbUser2?who=Insert" method="post">41 <h4>新增用户</h4>42 姓名: <input type="text" name="name"><br />43 密码: <input type="text" name="password"><br /> 44 出生日期 : <input type="text" name="birthday"><br /> 45 性别: <select name="sex">46 <option value="0">男</option>47 <option value="1">女</option>48 </select><br /> 49 <input type="submit" value="新增"/>50 <hr />51 </form>52 </div> 53 <div align="center"style="width: 400px; position: relative;left:450px;">54 <form action="${url}/zhu/Servlet_TbUser2?who=queryAll" method="post"> 55 <input type="submit" value="查询所有的数据"/> <br/>56 <table border="1" cellspacing="0"> 57 <thead>58 <tr><td>ID</td><td>姓名</td><td>密码</td><td>日期</td><td>性别</td><td>操作</td></tr>59 </thead>60 <tbody>61 <c:forEach items="${list}" var="list">62 <tr>63 <td>${list.id }</td>64 <td>${list.name }</td>65 <td>${list.password }</td>66 <td>${list.birthday }</td> 67 <td><c:if test="${list.sex==false }">男</c:if>68 <c:if test="${list.sex==true }">女</c:if></td>69 <td><a href= "${url}/zhu/Servlet_TbUser?who=queryById&id=${list.id}" style='text-decoration:none' >修改 </a> 70 <a href= "${url}/zhu/Servlet_TbUser?who=delete&id=${list.id}" style='text-decoration:none' >删除</a> </td> 71 </tr>72 </c:forEach>73 </tbody>74 </table>75 <hr />76 </form>77 </div> 78 79 <div align="center"80 style="width: 400px; position: relative;left:450px"> 81 <h4>不用使用form标签提交表单,使用jQuery的post来提交表单</h4>82 <h5>新增用户</h5> 83 姓名: <input type="text" id="name"><br />84 密码: <input type="text" id="password"><br /> 85 出生日期 : <input type="text" id="birthday"><br /> 86 性别: <select id="sex">87 <option value="0">男</option>88 <option value="1">女</option>89 </select><br /> 90 <input type="button" value="新增" onclick="funInsert()"/>91 <hr />92 93 </div> 94 </body>95 </html>Die Das für JSON* erforderliche JAR-Paket ist
1 package zhu.jdbc.servlet; 2 3 import java.io.IOException; 4 import java.sql.Date; 5 6 import java.text.SimpleDateFormat; 7 import java.util.List; 8 9 import javax.servlet.ServletException; 10 import javax.servlet.http.HttpServlet; 11 import javax.servlet.http.HttpServletRequest; 12 import javax.servlet.http.HttpServletResponse; 13 14 import net.sf.json.JSONObject; 15 16 17 18 import zhu.jdbc.domain.Tb_User; 19 import zhu.jdbc.service.ITb_UserService; 20 import zhu.jdbc.service.imp.ITb_UserServiceImpI; 21 import zhu.jdbc.unit.WebUtils; 22 23 public class Servlet_TbUser2 extends HttpServlet { 24 /** 25 *
26 */ 27 private static final long serialVersionUID = 1L; 28 ITb_UserService myITb_UserService = new ITb_UserServiceImpI(); 29 30 @Override 31 protected void doGet(HttpServletRequest req, HttpServletResponse resp) 32 throws ServletException, IOException { 33 doPost(req, resp); 34 } 35 36 @Override 37 protected void doPost(HttpServletRequest request, 38 HttpServletResponse response) throws ServletException, IOException { 39 request.setCharacterEncoding("UTF-8");// 解决乱码 40 String type = request.getParameter("who"); 41 // 新增 42 if ("Insert".equals(type)) { 43 Insert(request, response); 44 } 45 //查询所有数据 46 else if("queryAll".equals(type)){ 47 queryAll(request, response); 48 }
49 //使用jquery提交表单新增 50 else if("jQueryInsert".equals(type)){ 51 jQueryInsert(request, response); 52 }
53 } 54 55 // 新增 56 public void Insert(HttpServletRequest request, HttpServletResponse response) 57 throws ServletException, IOException { 58 /*注册字符串到日期的转换器
59 * ConvertUtils.register(new DateLocaleConverter(), java.util.Date.class);
60 * */
61 //将jsp页面专递参数封装到 domain层的 Tb_User对象中 62 Tb_User tb_User=WebUtils.request2Bean(request, Tb_User.class);
63 System.out.println(tb_User.getName());
64 // 把获取到的这些值放到user里 65 Tb_User user = new Tb_User(); 66 try { 67 // 下面两句是把 string 转换为 sql类型的 时间格式 68 SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); 69 String time=sdf.format(tb_User.getBirthday()); 70 user.setBirthday(new Date(sdf.parse(time).getTime())); 71 user.setEmail(tb_User.getEmail()); 72 user.setName(tb_User.getName()); 73 user.setPassword(tb_User.getPassword());
74 user.setSex(tb_User.isSex()); 75 // 最后调用服务来添加 76 String message = null; 77 if (myITb_UserService.insertData(user) == true) { 78 queryAll(request, response); 79 } else { 80 message = "新增失败!!!"; 81 request.setAttribute("msg", message); 82 request.getRequestDispatcher("/index.jsp").forward(request, response); 83 } 84 } catch (Exception e1) { 85 e1.printStackTrace(); 86 } 87 } 88 //查询所有的数据 89 public void queryAll(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException{ 90 List<Tb_User> lis=myITb_UserService.queryAllData();
91 request.setAttribute("list", lis); 92 request.getRequestDispatcher("/jsp/WebUtils_User.jsp").forward(request, response); 93 } 94 95 96 // 新增 97 public void jQueryInsert(HttpServletRequest request, HttpServletResponse response) 98 throws ServletException, IOException { 99 100 /*注册字符串到日期的转换器
101 * ConvertUtils.register(new DateLocaleConverter(), java.util.Date.class);
102 * */
103 //将jsp页面专递参数封装到 domain层的 Tb_User对象中104 Tb_User tb_User=WebUtils.request2Bean(request, Tb_User.class);
105 System.out.println(tb_User.getName());
106 // 把获取到的这些值放到user里107 Tb_User user = new Tb_User();108 try {109 // 下面两句是把 string 转换为 sql类型的 时间格式110 SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");111 String time=sdf.format(tb_User.getBirthday());112 user.setBirthday(new Date(sdf.parse(time).getTime()));113 user.setEmail(tb_User.getEmail());114 user.setName(tb_User.getName());115 user.setPassword(tb_User.getPassword());
116 user.setSex(tb_User.isSex());117 // 最后调用服务来添加
118 119 JSONObject json=new JSONObject();120 response.setCharacterEncoding("UTF-8");//解决乱码121 if (myITb_UserService.insertData(user) == true) {122 json.put("msg", "新增成功!");
123 } else {
124 json.put("msg", "新增失败!");
125 }126 //使用了JSONObject就必须这句代码
127 response.getWriter().write(json.toString());128 } catch (Exception e1) {129 e1.printStackTrace();130 }131 132 }133 134 }Quellcode-Download-Adresse: 
Das obige ist der detaillierte Inhalt vonDie Parameter des in JSP übermittelten Formulars werden in eine Methode gekapselt. Für weitere Informationen folgen Sie bitte anderen verwandten Artikeln auf der PHP chinesischen Website!
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