首页 > 代码库 > 编码实战Web端联系人的增删改查
编码实战Web端联系人的增删改查
首先画出分析图
实现效果如图
项目下的包如图:
实体包
package com.contactSystem.entiey; public class Contact { private String Id; private String name; private String sex; private String age; private String phone; private String qq; private String email; public String getId() { return Id; } public void setId(String id) { Id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } public String getAge() { return age; } public void setAge(String age) { this.age = age; } public String getPhone() { return phone; } public void setPhone(String phone) { this.phone = phone; } public String getQq() { return qq; } public void setQq(String qq) { this.qq = qq; } public String getEmail() { return email; } public void setEmail(String email) { this.email = email; } @Override public String toString() { return "Contact [Id=" + Id + ", name=" + name + ", sex=" + sex + ", age=" + age + ", phone=" + phone + ", qq=" + qq + ", email=" + email + "]"; } }
XML的工具包(只是避免了代码的重复使用,将其放进工具包中)
package com.contactSystem.util; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.OutputStream; import javax.management.RuntimeErrorException; import org.dom4j.Document; import org.dom4j.DocumentException; import org.dom4j.io.OutputFormat; import org.dom4j.io.SAXReader; import org.dom4j.io.XMLWriter; /* * xml操作的工具类 */ public class XMLUtil { //写出一个xml文件 public static void write2xml(Document doc) throws Exception{ OutputStream out=new FileOutputStream("e:/contact.xml"); OutputFormat format=OutputFormat.createPrettyPrint(); format.setEncoding("utf-8"); XMLWriter writer=new XMLWriter(out,format); writer.write(doc); writer.close(); } //读取本地xml文件的方法 public static Document getDocument(){ Document doc; try { doc = new SAXReader().read("e:/contact.xml"); return doc; } catch (DocumentException e) { // TODO Auto-generated catch block e.printStackTrace(); throw new RuntimeException(e); } } }
抽象的接口
package com.contactSystem.dao; import java.io.FileNotFoundException; import java.io.UnsupportedEncodingException; import java.util.List; import org.dom4j.DocumentException; import com.contactSystem.entiey.Contact; public interface ContactOperate { public void addContact(Contact contact) throws Exception; public void updateContact(Contact contact) throws Exception; public void removeContact(String id) throws Exception; public Contact findContact(String id) throws Exception; public List<Contact> allContacts(); }
具体的实现方法和操作
package com.contactSystem.dao.daoImpl; import java.io.File; import java.util.ArrayList; import java.util.List; import java.util.UUID; import javax.persistence.Id; import org.dom4j.Document; import org.dom4j.DocumentHelper; import org.dom4j.Element; import org.dom4j.io.SAXReader; import com.contactSystem.dao.ContactOperate; import com.contactSystem.entiey.Contact; import com.contactSystem.util.XMLUtil; public class Operater implements ContactOperate { @Override //添加联系人 public void addContact(Contact contact) throws Exception { // TODO Auto-generated method stub File file=new File("e:/contact.xml"); Document doc=null; Element rootElem=null; if (file.exists()) { doc=new SAXReader().read(file); rootElem=doc.getRootElement(); }else { doc=DocumentHelper.createDocument(); rootElem=doc.addElement("ContactList"); } //开始添加个体 Element element=rootElem.addElement("contact"); //有系统自动生成一随机且唯一的ID,赋给联系人Id,系统提供了一个包UUID包 String uuid=UUID.randomUUID().toString().replace("-", ""); element.addAttribute("Id", uuid); element.addElement("姓名").setText(contact.getName()); element.addElement("name").setText(contact.getName()); element.addElement("sex").setText(contact.getSex()); element.addElement("age").setText(contact.getAge()); element.addElement("phone").setText(contact.getPhone()); element.addElement("email").setText(contact.getEmail()); element.addElement("qq").setText(contact.getQq()); //写入到本地的xml文档中 XMLUtil.write2xml(doc); } @Override public void updateContact(Contact contact) throws Exception { // TODO Auto-generated method stub //通过xpath查找对应id的联系人 Document document=XMLUtil.getDocument(); Element element=(Element) document.selectSingleNode("//contact[@Id=‘"+contact.getId()+"‘]"); //根据标签改文本 System.out.println(element); element.element("name").setText(contact.getName()); element.element("age").setText(contact.getAge()); element.element("email").setText(contact.getEmail()); element.element("phone").setText(contact.getPhone()); element.element("sex").setText(contact.getSex()); element.element("qq").setText(contact.getQq()); XMLUtil.write2xml(document); } @Override public void removeContact(String id) throws Exception { // TODO Auto-generated method stub //通过xpath去查找对应的contact Document document=XMLUtil.getDocument(); Element element=(Element) document.selectSingleNode("//contact[@Id=‘"+id+"‘]"); /** * 如果是火狐浏览器,其本身有一个bug,对于一个get请求,它会重复做两次, * 第一次会把一个唯一的id给删除掉,但是在第二次的时候,它会继续去删,而这个时候查找不到,会报错,会发生错误, * 为了解决这个bug,我们在这里验证其是否为空 */ if (element!=null) { element.detach(); XMLUtil.write2xml(document); } } @Override public Contact findContact(String id) throws Exception { // TODO Auto-generated method stub Document document=XMLUtil.getDocument(); Element e=(Element) document.selectSingleNode("//contact[@Id=‘"+id+"‘]"); Contact contact=null; if (e!=null) { contact=new Contact(); contact.setAge(e.elementText("age")); contact.setEmail(e.elementText("email")); contact.setId(e.attributeValue("id")); contact.setName(e.elementText("name")); contact.setPhone(e.elementText("phone")); contact.setSex(e.elementText("sex")); contact.setQq(e.elementText("qq")); } return contact; } @Override public List<Contact> allContacts() { // TODO Auto-generated method stub Document document=XMLUtil.getDocument(); List<Contact> list=new ArrayList<Contact>(); List<Element> conElements=(List<Element>)document.selectNodes("//contact"); for (Element element : conElements) { Contact contact=new Contact(); contact.setId(element.attributeValue("Id")); contact.setAge(element.elementText("age")); contact.setEmail(element.elementText("email")); contact.setName(element.elementText("name")); contact.setPhone(element.elementText("phone")); contact.setQq(element.elementText("qq")); contact.setSex(element.elementText("sex")); list.add(contact); } return list; } }
添加联系人的html页面
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>添加联系人</title> <style media="screen"> #btn{ width:40px; width: 50px; background: green; color: white; font-size:14px; } </style> </head> <body> <center> <h2>添加联系人</h2> </center> <form action="/ContactWeb/addServlet" method="post"> <table border="1" align="center"> <tbody> <tr> <th>姓名</th> <td><input type="text" name="userName" /></td> </tr> <tr> <th>年龄</th> <td><input type="text" name="age" /></td> </tr> <tr> <th>性别</th> <td> <input type="radio" name="sex" value="http://www.mamicode.com/男"/>男 <input type="radio" name="sex" value="http://www.mamicode.com/女" />女 </td> </tr> <tr> <th>电话</th> <td><input type="text" name="phone" /></td> </tr> <tr> <th>QQ</th> <td><input type="text" name="qq" /></td> </tr> <tr> <th>邮箱</th> <td><input type="text" name="email" /></td> </tr> <tr> <td colspan="3" align="center"> <input type="submit" value="http://www.mamicode.com/提交" id="btn"/> </td> </tr> </tbody> </table> </form> </body> </html>
接下来则是最重要的servlet(显示首页,所有联系人)
package com.contactSystem.servlet; import java.io.IOException; import java.io.PrintWriter; import java.util.ArrayList; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.contactSystem.dao.daoImpl.Operater; import com.contactSystem.entiey.Contact; public class Index extends HttpServlet { /** * 显示所有联系人的逻辑方式 */ private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=utf-8"); Operater operater=new Operater(); List<Contact> contacts=operater.allContacts(); PrintWriter writer=response.getWriter(); /** * shift+alt+A ——>区域选择 * 正则表达式:“."表示任意字符,"*"表示多个字符 * “/1”表示一行代表匹配一行内容 */ String html=""; html+= "<!DOCTYPE html>"; html+= "<html>"; html+= ""; html+= "<head>"; html+= " <meta charset=‘utf-8‘>"; html+= " <title>查询所有联系人</title>"; html+= " <style media=‘screen‘>"; html+= " table td {"; html+= " text-align: center;"; html+= " }"; html+= ""; html+= " table {"; html+= " border-collapse: collapse;"; html+= " }"; html+= " </style>"; html+= "</head>"; html+= ""; html+= "<body>"; html+= " <center>"; html+= " <h2>查询所有联系人</h2>"; html+= " </center>"; html+= " <table border=‘1‘ align=‘center‘>"; html+= " <tbody>"; html+= " <thead>"; html+= " <th>编号</th>"; html+= " <th>姓名</th>"; html+= " <th>性别</th>"; html+= " <th>年龄</th>"; html+= " <th>电话</th>"; html+= " <th>QQ</th>"; html+= " <th>邮箱</th>"; html+= " <th>操作</th>"; html+= " </thead>"; html+= " "; html+= " <tr>"; if (contacts!=null) { for (Contact contact : contacts) { html+= " <td>"+contact.getId()+"</td>"; html+= " <td>"+contact.getName()+"</td>"; html+= " <td>"+contact.getSex()+"</td>"; html+= " <td>"+contact.getAge()+"</td>"; html+= " <td>"+contact.getPhone()+"</td>"; html+= " <td>"+contact.getQq()+"</td>"; html+= " <td>"+contact.getEmail()+"</td>"; html+= " <td><a href=http://www.mamicode.com/‘"+request.getContextPath()+"/FindIdServlet?id="+contact.getId()+"‘>修改</a> <a href=http://www.mamicode.com/‘"+request.getContextPath()+"/DeleteServlet?id="+contact.getId()+"‘>删除</a></td>"; html+= " </tr>"; } } html+= " <tr>"; html+= " <td colspan=‘8‘>"; html+= " <a href=http://www.mamicode.com/‘"+request.getContextPath()+"/add.html‘‘‘>添加联系人</a>"; html+= " </td>"; html+= " </tr>"; html+= " </tbody>"; html+= " </table>"; html+= "</body>"; html+= ""; html+= "</html>"; writer.write(html); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request, response); } }
添加联系人的servlet
package com.contactSystem.servlet; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.contactSystem.dao.daoImpl.Operater; import com.contactSystem.entiey.Contact; public class addServlet extends HttpServlet { /** * 处理添加联系人的逻辑 */ private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); String userName=request.getParameter("userName"); String age=request.getParameter("age"); String sex=request.getParameter("sex"); String phone=request.getParameter("phone"); String qq=request.getParameter("qq"); String email=request.getParameter("email"); Operater operater=new Operater(); Contact contact=new Contact(); contact.setName(userName); contact.setAge(age); contact.setSex(sex); contact.setPhone(phone); contact.setQq(qq); contact.setEmail(email); try { operater.addContact(contact); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } response.sendRedirect(request.getContextPath()+"/Index"); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request, response); } }
修改联系人,根据查找到的联系人,显示在其上面如图(根据显示的首页显示得内容为本页面的默认值)
首先是要去查找这个联系人的信息,即FindIdServlet
package com.contactSystem.servlet; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.contactSystem.dao.daoImpl.Operater; import com.contactSystem.entiey.Contact; public class FindIdServlet extends HttpServlet { /** * 修改联系人逻辑 */ private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=utf-8"); PrintWriter writer=response.getWriter(); Operater operater=new Operater(); String id=request.getParameter("id"); Contact contact=null; try { contact=operater.findContact(id); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } String html=""; html += "<!DOCTYPE html>"; html += "<html>"; html += "<head>"; html += " <meta charset=‘utf-8‘>"; html += " <title>添加联系人</title>"; html += " <style media=‘screen‘>"; html += " #btn{"; html += " width:40px;"; html += " width: 50px;"; html += " background: green;"; html += " color: white;"; html += " font-size:14px;"; html += " }"; html += " </style>"; html += "</head>"; html += ""; html += "<body>"; html += " <center>"; html += " <h2>修改联系人</h2>"; html += " </center>"; html += " <form action=‘"+request.getContextPath()+"/UpdateServlet‘ method=‘post‘>"; html +="<input type=‘hidden‘ name=‘id‘ value=http://www.mamicode.com/‘"+id+"‘ />"; html += " <table border=‘1‘ align=‘center‘>"; html += " <tbody>"; html += " <tr>"; html += " <th>姓名</th>"; html += " <td><input type=‘text‘ name=‘userName‘ value=http://www.mamicode.com/‘"+contact.getName()+"‘/></td>"; html += " </tr>"; html += " <tr>"; html += " <th>年龄</th>"; html += " <td><input type=‘text‘ name=‘age‘ value=http://www.mamicode.com/‘"+contact.getAge()+"‘ /></td>"; html += " </tr>"; html += " <tr>"; html += " <th>性别</th>"; html += " <td>"; if (contact.getSex().equals("男")) { html += " <input type=‘radio‘ name=‘sex‘ value=http://www.mamicode.com/‘男‘ checked=‘checked‘/>男 "; html += " <input type=‘radio‘ name=‘sex‘ value=http://www.mamicode.com/‘女‘ />女"; }else { html += " <input type=‘radio‘ name=‘sex‘ value=http://www.mamicode.com/‘男‘ />男 "; html += " <input type=‘radio‘ name=‘sex‘ value=http://www.mamicode.com/‘女‘ checked=‘checked‘ />女"; } html += " </td>"; html += " </tr>"; html += " <tr>"; html += " <th>电话</th>"; html += " <td><input type=‘text‘ name=‘phone‘ value=http://www.mamicode.com/‘"+contact.getPhone()+"‘ /></td>"; html += " </tr>"; html += " <tr>"; html += " <th>QQ</th>"; html += " <td><input type=‘text‘ name=‘qq‘ value=http://www.mamicode.com/‘"+contact.getQq()+"‘ /></td>"; html += " </tr>"; html += " <tr>"; html += " <th>邮箱</th>"; html += " <td><input type=‘text‘ name=‘email‘ value=http://www.mamicode.com/‘"+contact.getEmail()+"‘ /></td>"; html += " </tr>"; html += " <tr>"; html += " <td colspan=‘3‘ align=‘center‘>"; html += " <input type=‘submit‘ value=http://www.mamicode.com/‘提交‘ id=‘btn‘/>"; html += " </td>"; html += " </tr>"; html += " </tbody>"; html += " </table>"; html += " </form>"; html += "</body>"; html += ""; html += "</html>"; writer.write(html); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request, response); } }
然后则是根据提交的内容去修改本地的联系人
package com.contactSystem.servlet; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.contactSystem.dao.daoImpl.Operater; import com.contactSystem.entiey.Contact; public class UpdateServlet extends HttpServlet { /** * 将修改后的数据提交 */ private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); request.setCharacterEncoding("utf-8"); String userName=request.getParameter("userName"); System.out.println(userName); String age=request.getParameter("age"); String sex=request.getParameter("sex"); String phone=request.getParameter("phone"); String qq=request.getParameter("qq"); String email=request.getParameter("email"); String id=request.getParameter("id"); Operater operater=new Operater(); Contact contact=new Contact(); contact.setId(id); contact.setName(userName); contact.setAge(age); contact.setSex(sex); contact.setPhone(phone); contact.setQq(qq); contact.setEmail(email); try { operater.updateContact(contact); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } response.sendRedirect(request.getContextPath()+"/Index"); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request, response); } }
最后则是删除联系人,不过要注意的是:火狐浏览器如果判断是get请求的话,会向服务器发送两次请求,可能会导致一些问题,其他的浏览器不会出出现该问题
package com.contactSystem.servlet; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.contactSystem.dao.daoImpl.Operater; public class DeleteServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=utf-8"); String id=request.getParameter("id"); Operater operater=new Operater(); try { operater.removeContact(id); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } response.sendRedirect(request.getContextPath()+"/Index"); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request, response); } }
最后:不用jsp去写,就用servlet去写html真的好累,还是好好学jsp吧。
编码实战Web端联系人的增删改查
声明:以上内容来自用户投稿及互联网公开渠道收集整理发布,本网站不拥有所有权,未作人工编辑处理,也不承担相关法律责任,若内容有误或涉及侵权可进行投诉: 投诉/举报 工作人员会在5个工作日内联系你,一经查实,本站将立刻删除涉嫌侵权内容。