通讯录改造——MVC设计模式

将之前用servlet写的程序转化为jsp+servlet的简单的MVC的三层结构。项目中程序的包如图


首先是实体对象:

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 + "]";
	}

}

然后就是对数据操作的抽象类

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();
	//根据名称姓名查询是否有存在重复。
	public boolean checkIfContact(String name);
}

具体实现类

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 javax.persistence.Tuple;

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(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;
	}
	/**
	 * true:说明重复
	 * false:说明没有重复
	 */
	@Override
	public boolean checkIfContact(String name) {
		// TODO Auto-generated method stub
		//查询name标签是否一样
		Document doc=XMLUtil.getDocument();
		Element element=(Element) doc.selectSingleNode("//name[text()='"+name+"']");
		if (element!=null) {
			return true;
		}else {
			return false;
		}

	}

}

为了减轻Servlet的负担在增加一层(业务逻辑层)Service,这里举例,当联系人的名字存在时,提示出错,不在servlet中去判断,而在service中去处理,同样首先写出service抽象接口

package com.contactSystem.service;

import java.util.List;

import com.contactSystem.entiey.Contact;

public interface ContactService {
	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();
}

这个时候有点相当于在Operate操作中添加了一层操作,在contactService的实现类中去有逻辑判断的去使用Operater的方法

package com.contactSystem.service.imple;

import java.util.List;

import com.contactSystem.dao.daoImpl.Operater;
import com.contactSystem.entiey.Contact;
import com.contactSystem.exception.NameRepeatException;
import com.contactSystem.service.ContactService;
/**
 * 处理项目中出现的业务逻辑
 * @author Administrator
 *
 */
public class ContactServiceImpe implements ContactService {
	Operater operater =new Operater();
	@Override
	public void addContact(Contact contact) throws Exception {
		// TODO Auto-generated method stub
		//执行业务逻辑判断
		/**
		 * 添加是否重复的业务逻辑
		 */
		if (operater.checkIfContact(contact.getName())) {
			//重复
			/**
			 * 注意:如果业务层方法出现任何错误,则返回标记(自定义的异常)到servlet
			 */
			 throw new NameRepeatException("姓名重复,不可使用");
		}
		operater.addContact(contact);

	}

	@Override
	public void updateContact(Contact contact) throws Exception {
		// TODO Auto-generated method stub
		operater.updateContact(contact);
	}

	@Override
	public void removeContact(String id) throws Exception {
		// TODO Auto-generated method stub
		operater.removeContact(id);
	}

	@Override
	public Contact findContact(String id) throws Exception {
		// TODO Auto-generated method stub
		return operater.findContact(id);
	}

	@Override
	public List<Contact> allContacts() {
		// TODO Auto-generated method stub
		return operater.allContacts();
	}

}

这里通过抛出异常去将信息传递给Servlet,异常代码如下

package com.contactSystem.exception;
/**
 * 姓名重复的自定义异常
 * @author Administrator
 *
 */
public class NameRepeatException extends Exception{
	public NameRepeatException(String msg) {
		super(msg);
	}
}

现在来写Servlet,首先是首页的联系人列表Servlet

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;
import com.contactSystem.service.ContactService;
import com.contactSystem.service.imple.ContactServiceImpe;

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");
		ContactService service=new ContactServiceImpe();
		List<Contact> contacts=service.allContacts();

		
		/**
		 * 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
		 */
		
		request.setAttribute("contacts", contacts);
		request.getRequestDispatcher("/index.jsp").forward(request, response);
		
	}


	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		this.doGet(request, response);
	}

}

添加联系人

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;
import com.contactSystem.exception.NameRepeatException;
import com.contactSystem.service.ContactService;
import com.contactSystem.service.imple.ContactServiceImpe;

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");
		
		ContactService service=new ContactServiceImpe();

		Contact contact=new Contact();
		contact.setName(userName);
		contact.setAge(age);
		contact.setSex(sex);
		contact.setPhone(phone);
		contact.setQq(qq);
		contact.setEmail(email);
		try {
			service.addContact(contact);
		} catch (NameRepeatException e) {
			// TODO Auto-generated catch block
			//处理名字重复的异常
			request.setAttribute("message", e.getMessage());
			request.getRequestDispatcher("/add.jsp").forward(request, response);
			return;
		} 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);
	}

}

查找联系人

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;
import com.contactSystem.service.ContactService;
import com.contactSystem.service.imple.ContactServiceImpe;

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");
		
		ContactService service=new ContactServiceImpe();
		
		String id=request.getParameter("id");
		
		Contact contact=null;
		try {
			contact=service.findContact(id);
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	
		request.setAttribute("contact", contact);
		request.getRequestDispatcher("/update.jsp").forward(request, response);
	}

	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		this.doGet(request, response);
	}

}

修改联系人

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;
import com.contactSystem.service.ContactService;
import com.contactSystem.service.imple.ContactServiceImpe;

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");
		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");
		ContactService service=new ContactServiceImpe();
		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 {
			service.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);
	}

}

删除联系人

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.service.ContactService;
import com.contactSystem.service.imple.ContactServiceImpe;

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");
		ContactService service=new ContactServiceImpe();
		try {
			service.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);
	}
}

以上完成了MVC的M和C,还差View,现在来具体显示jsp页面

首页所有联系人的显示

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>

<head>
    <meta charset='utf-8'>
    <title>查询所有联系人</title>
    <style media='screen'>
        table td {
            text-align: center;
        }

        table {
            border-collapse: collapse;
        }
    </style>
</head>

<body>
    <center>
        <h2>查询所有联系人</h2>
    </center>
    <table border='1' align='center'>
        <tbody>
            <thead>
                <th>编号</th>
                <th>姓名</th>
                <th>性别</th>
                <th>年龄</th>
                <th>电话</th>
                <th>QQ</th>
                <th>邮箱</th>
                <th>操作</th>
            </thead>
           <c:forEach items="${contacts}" var="con"  varStatus="varSta">
            <tr>
                <td>${varSta.count }</td>
                <td>${con.name }</td>
                <td>${con.sex }</td>
                <td>${con.age }</td>
                <td>${con.phone }</td>
                <td>${con.qq }</td>
                <td>${con.email }</td>
                <td><a href='${pageContext.request.contextPath }/FindIdServlet?id=${con.id}'>修改</a>  <a href='${pageContext.request.contextPath }/DeleteServlet?id=${con.id}'>删除</a></td>
            </tr>
            </c:forEach>
            <tr>
                <td colspan='8'>
                    <a href='${pageContext.request.contextPath}/add.jsp'>添加联系人</a>
                </td>
            </tr>
        </tbody>
    </table>
</body>

</html>

  

修改联系人,首先要把要修改联系人的信息都显示在信息栏中,然后用户去修改相关信息

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <title>修改联系人</title>
    <style media="screen">
      #btn{
        40px;
         50px;
        background: green;
        color: white;
        font-size:14px;
      }
    </style>
</head>

<body>
    <center>
        <h2>修改联系人</h2>
    </center>
    <form action="${pageContext.request.contextPath }/UpdateServlet" method="post">
        <table border="1" align="center">
            <tbody>
                
                <tr>
                    <th>姓名</th>
                    <td><input type="text" name="userName" value="${contact.name}"/></td>
                    <input type="hidden" name="id" value="${contact.id }"/>
                    
                </tr>
                <tr>
                    <th>年龄</th>
                    <td><input type="text" name="age" value="${contact.age }" /></td>
                </tr>
                <tr>
                  <th>性别</th>
                  <td>
                  	
                    <input type="radio" name="sex"  value="男" <c:if test="${contact.sex=='男' }"> checked="true"</c:if>/>男  
                    <input type="radio" name="sex" value="女" <c:if test="${contact.sex=='女' }"> checked="true"</c:if> />女
                  </td>
                </tr>
                <tr>
                    <th>电话</th>
                    <td><input type="text" name="phone" value="${contact.phone }" /></td>
                </tr>
                <tr>
                    <th>QQ</th>
                    <td><input type="text" name="qq" value="${contact.qq }" /></td>
                </tr>
                <tr>
                    <th>邮箱</th>
                    <td><input type="text" name="email" value="${contact.email }" /></td>
                </tr>
                <tr>
                  <td colspan="3" align="center">
                    <input type="submit"  value="提交" id="btn"/>
                  </td>
                </tr>
            </tbody>
        </table>
    </form>
</body>

</html>

  

最后就是添加联系人了

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <title>添加联系人</title>
    <style media="screen">
      #btn{
        40px;
         50px;
        background: green;
        color: white;
        font-size:14px;
      }
    </style>
</head>

<body>
    <center>
        <h2>添加联系人</h2>
    </center>
    <form action="${pageContext.request.contextPath}/addServlet" method="post">
        <table border="1" align="center">
            <tbody>
           
                <tr>
                    <th>姓名</th>
                    <td><input type="text" name="userName" value="${message }" /></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="男"/>男  
                    <input type="radio" name="sex" value="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="提交" id="btn"/>
                  </td>
                </tr>
            </tbody>
        </table>
    </form>
</body>

</html>

最后可以加上一个测试类,方便自己调试

package com.contactSystem.Junit;

import static org.junit.Assert.*;

import java.util.List;

import org.junit.Before;

import com.contactSystem.dao.daoImpl.Operater;
import com.contactSystem.entiey.Contact;


public class Test {
Operater operator=null;
	
	//初始化这个对象的实例
	@Before
	public void init(){
		 operator=new Operater();
	}
	
	@org.junit.Test
	public void Add() throws Exception{
		Contact contact=new  Contact();

		contact.setAge("21");
		contact.setEmail("454444@qq.com");
		contact.setName("gqxing");
		contact.setPhone("13455555");
		contact.setQq("235346662");
		contact.setSex("男");
		operator.addContact(contact);
	}
	
	@org.junit.Test
	public void update() throws Exception{
		Contact contact=new  Contact();
		contact.setId("002");
		contact.setAge("0");
		contact.setEmail("0000000@qq.com");
		contact.setName("test");
		contact.setPhone("0-00000000000");
		contact.setQq("000000000000");
		contact.setSex("男");
		operator.updateContact(contact);
	}
	
	
	@org.junit.Test
	public void removeContact() throws Exception{
		operator.removeContact("002");
	}
	
	@org.junit.Test
	public void findContact() throws Exception{
		Contact contact=operator.findContact("002");
		System.out.println(contact);
	}
	
	@org.junit.Test
	public void allContact() throws Exception{
		List<Contact> contacts= operator.allContacts();
		for (Contact contact : contacts) {
			System.out.println(contact);
		}
	}
	@org.junit.Test
	public void TetsCheckBoolean() throws Exception{
		Boolean flag=operator.checkIfContact("郭庆兴");
		System.out.println(flag);
	}
	
	
}

最后运行的结构示意图:

当名字重复的时候:提交就会显示

原文地址:https://www.cnblogs.com/helloworldcode/p/6067533.html