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mvc02

2023-11-30 43
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简介： mvc02
  • 三次优化

三次优化

根据mvc01可知它的弊端：

package com.zhulinjun.web;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.zhulinjun.framework.Action;
public class orderAction extends Action{
  public void add(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("orderAction.add..");
    }
  public void del(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("orderAction.del..");
    }
  public void upd(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("orderAction.upd..");
    }
  public void list(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("orderAction.list..");
    }
}
package com.zhulinjun.framework;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletConfig;
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 com.zhulinjun.web.bookAction;
import com.zhulinjun.web.orderAction;
/**
 * 对应图中的ActionServlet：中央控制器
 * @author 朱
 */
@WebServlet("*.action")
public class DispatcherServlet extends HttpServlet{
public Map<String, Action> actionMap=new HashMap<String, Action>();
@Override
public void init(ServletConfig config) throws ServletException {
  actionMap.put("/order", new orderAction());
  super.init(config);
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//http://locahost:80/mvc/book.action?methodName=add
String uri = req.getRequestURI();
uri= uri.substring(uri.lastIndexOf("/"),uri.lastIndexOf("."));
Action action = actionMap.get(uri);
action.excute(req, resp);
}
}
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<a href="order.action?methodName=add">增加</a>
<a href="order.action?methodName=del">删除</a>
<a href="order.action?methodName=upd">修改</a>
<a href="order.action?methodName=list">查询</a>
</body>
</html>

1.第一次优化，版本5，将中央控制器中的action容器加载变成可配置

以前所有的子控制器是放到map集合中，现在所有的子控制器在mvc.xml中，其实就是放到configModel

常识：查询必然转发，增删改使用重定向

弊端：中央控制器中的action容器加载不可以灵活配置

package com.zhulinjun.model;
import java.io.InputStream;
import java.util.List;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
public class ConfigModelFactory {
  public static ConfigModel build(String xmlPath) throws Exception {
    ConfigModel configModel = new ConfigModel();
    InputStream in = ConfigModelFactory.class.getResourceAsStream(xmlPath);
    SAXReader sr = new SAXReader();
    Document doc = sr.read(in);
//    System.out.println(doc.asXML());
//    configModel要有类容，就意味着actionmodel要有类容，然后放入到configmodel中去
    List<Element> actionEles = doc.selectNodes("/config/action");
    for (Element actionEle : actionEles) {
//      System.out.println(actionEle.asXML());
      ActionModel actionModel = new ActionModel();
      actionModel.setPath(actionEle.attributeValue("path"));
      actionModel.setType(actionEle.attributeValue("type"));
//      actionModel要有forwardModel，就意味着forwardmodel要有类容，然后放入到actionmodel中去
      List<Element> forwardEles = actionEle.selectNodes("forward");
      for (Element forwardEle : forwardEles) {
        System.out.println(forwardEle.asXML());
        ForwardModel forwardModel = new ForwardModel();
        forwardModel.setName(forwardEle.attributeValue("name"));
        forwardModel.setPath(forwardEle.attributeValue("path"));
//        只有填写false才是转发，其它都为重定向
//        forwardModel.setRedirect(false);
        forwardModel.setRedirect(!"false".equals(forwardEle.attributeValue("redirect")));
        actionModel.push(forwardModel);
      }
      configModel.push(actionModel);
    }
    return configModel;
  }
  public static ConfigModel build() throws Exception {
    return build("/mvc.xml");
  }
  public static void main(String[] args) throws Exception {
    ConfigModelFactory.build();
  }
}
package com.zhulinjun.model;
import java.util.HashMap;
import java.util.Map;
public class ActionModel {
private String path;
private String type;
private Map<String, ForwardModel> fMap=new HashMap<String, ForwardModel>();
public String getPath() {
  return path;
}
public void setPath(String path) {
  this.path = path;
}
public String getType() {
  return type;
}
public void setType(String type) {
  this.type = type;
}
//将forward往action中放    压栈
public void push(ForwardModel forwardModel) {
  fMap.put(forwardModel.getName(), forwardModel);
}
//  从action中通过name值取出forward
public ForwardModel pop(String name) {
  return fMap.get(name);
}
}
package com.zhulinjun.model;
import java.util.HashMap;
import java.util.Map;
import org.dom4j.DocumentException;
public class ConfigModel {
  private Map<String, ActionModel> aMap = new HashMap<String, ActionModel>();
  public void push(ActionModel actionModel) {
    aMap.put(actionModel.getPath(), actionModel);
  }
  public ActionModel pop(String path) {
    return aMap.get(path);
  }
  public static void main(String[] args) throws Exception {
    ConfigModel configModel = new ConfigModelFactory().build();
    ActionModel ActionModel = configModel.pop("/regAction");
    ForwardModel forwardModel = ActionModel.pop("success");
    System.out.println(forwardModel.getPath());
  }
}
package com.zhulinjun.framework;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletConfig;
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 org.dom4j.DocumentException;
import com.zhulinjun.model.ActionModel;
import com.zhulinjun.model.ConfigModel;
import com.zhulinjun.model.ConfigModelFactory;
import com.zhulinjun.model.ForwardModel;
@WebServlet("*.action")
public class DispatcherServlet extends HttpServlet {
  public Map<String, Action> actionMap = new HashMap<String, Action>();
  // 以前所有的子控制器是放到map集合中，现在所有的子控制器在mvc.xml中，其实就是放到configModel
  private ConfigModel configModel;
  @Override
  public void init(ServletConfig config) throws ServletException {
    // actionMap.put("/book", new bookAction());
    // actionMap.put("/order", new orderAction());
      try {
        configModel=ConfigModelFactory.build();
      } catch (Exception e) {
        e.printStackTrace();
      }
    super.init(config);
  }
  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    this.doPost(request, response);
  }
  @Override
  protected void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    // http://locahost:80/mvc/book.action?methodName=add
    String uri = request.getRequestURI();
//    System.out.println(uri);
    uri = uri.substring(uri.lastIndexOf("/"), uri.lastIndexOf("."));
//    System.out.println("url" + uri);
    // Action action = actionMap.get(uri);
    // 通过uri=/book，在configModel对象中找
    ActionModel actionMondel = configModel.pop(uri);
//    System.out.println(actionMondel + "" + "actionMondel");
    if (actionMondel == null)
      throw new RuntimeException("action not config");
    // com.zking.web.BookAction
    String type = actionMondel.getType();
    // BookAction bookaction=new BookAction();
      action = (Action) Class.forName(type).newInstance();
      action.execute(request, response);
  }
}
package com.zhulinjun.framework;
import java.io.IOException;
import java.lang.reflect.Method;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * 子控制器
 * 正真做事，处理浏览器发送的请求的类
 * @author 朱
 *
 */
public class Action {
  protected String execute(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    String methodName = request.getParameter("methodName");   
    String res="";
    try {
      Method m = this.getClass().getDeclaredMethod(methodName, HttpServletRequest.class,HttpServletResponse.class);
//      System.out.println("m"+m);
      m.setAccessible(true);
      res=(String) m.invoke(this, request,response);
    } catch (Exception e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
    return res;
  }
}

2.第二次优化，针对于反射调用业务代码，最终页面跳转代码优化

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<p>版本5</p>
<a href="book.action?methodName=add">增加</a>
<a href="book.action?methodName=del">删除</a>
<a href="book.action?methodName=upd">修改</a>
<a href="book.action?methodName=list">查询</a>
</body>
</html>
package com.zhulinjun.web;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.zhulinjun.framework.Action;
public class bookAction extends Action{
  public String add(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("bookAction.add..5");
    request.setAttribute("content", "你好");
//    response.sendRedirect("res.jsp");
    return "toList";
    }
  public String del(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("bookAction.del..5");
    request.setAttribute("content", "你好");
//    response.sendRedirect("res.jsp");
    return "toList";
    }
  public String upd(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("bookAction.upd..5");
    request.setAttribute("content", "你好");
//    response.sendRedirect("res.jsp");
    return "toList";
    }
  public String list(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("bookAction.list..");
    request.setAttribute("content", "你好");
//    request.getRequestDispatcher("res.jsp").forward(request, response);
    return "list";  
  }
}
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
跳转成功：携带数据${content }
</body>
</html>
package com.zhulinjun.framework;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletConfig;
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 org.dom4j.DocumentException;
import com.zhulinjun.model.ActionModel;
import com.zhulinjun.model.ConfigModel;
import com.zhulinjun.model.ConfigModelFactory;
import com.zhulinjun.model.ForwardModel;
@WebServlet("*.action")
public class DispatcherServlet extends HttpServlet {
  public Map<String, Action> actionMap = new HashMap<String, Action>();
  // 以前所有的子控制器是放到map集合中，现在所有的子控制器在mvc.xml中，其实就是放到configModel
  private ConfigModel configModel;
  @Override
  public void init(ServletConfig config) throws ServletException {
    // actionMap.put("/book", new bookAction());
    // actionMap.put("/order", new orderAction());
      try {
        configModel=ConfigModelFactory.build();
      } catch (Exception e) {
        e.printStackTrace();
      }
    super.init(config);
  }
  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    this.doPost(request, response);
  }
  @Override
  protected void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    // http://locahost:80/mvc/book.action?methodName=add
    String uri = request.getRequestURI();
//    System.out.println(uri);
    uri = uri.substring(uri.lastIndexOf("/"), uri.lastIndexOf("."));
//    System.out.println("url" + uri);
    // Action action = actionMap.get(uri);
    // 通过uri=/book，在configModel对象中找
    ActionModel actionMondel = configModel.pop(uri);
//    System.out.println(actionMondel + "" + "actionMondel");
    if (actionMondel == null)
      throw new RuntimeException("action not config");
    // com.zking.web.BookAction
    String type = actionMondel.getType();
    // BookAction bookaction=new BookAction();
    Action action;
    try {
      action = (Action) Class.forName(type).newInstance();
//      具体业务代码执行后的返回值 add/upd/del/list的返回值j==>list/tolist
      String res = action.execute(request, response);
//            要通过返回值拿到，该方法结果是重定向还是转发，还是跳转哪个页面
      ForwardModel forwardModel = actionMondel.pop(res);
      if(forwardModel!=null){
        boolean redirect=forwardModel.isRedirect();
        String path=forwardModel.getPath();
        if(redirect) {
          response.sendRedirect(request.getContextPath() + "/" + path);
        }else {
          request.getRequestDispatcher(path).forward(request, response);
        }
      }
    } catch (Exception e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
  }
}

3.jsp页面参数页面传递后台的代码优化

弊端：jsp传递到后台，封装到实体类的代码过多

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<p>版本7</p>
<a href="book.action?methodName=add&bid=1&bname=nb&price=9.9">增加</a>
<a href="book.action?methodName=del">删除</a>
<a href="book.action?methodName=upd">修改</a>
<a href="book.action?methodName=list">查询</a>
</body>
</html>
package com.zhulinjun.web;
import java.io.IOException;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.zhulinjun.entity.Book;
import com.zhulinjun.framework.Action;
import com.zhulinjun.model.MondelDriver;
public class bookAction extends Action implements MondelDriver<Book>{
  private Book book=new Book();
  public String add(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    Map<String, String[]> parameterMap = request.getParameterMap();
    /*
     * 1.要有表对应的属性对象Book book
     * 2.获取到所有的参数及参数req.getparamentMap();
     * 3.将参数值封装到对应的对象中
     * 4.要做到所有的子控制器通用
     */
//    String bid=request.getParameter("bid");
//    String bname = request.getParameter("bname");
//    String price=request.getParameter("price");
//    Book book=new Book();
//    book.setBid(Integer.valueOf(bid));
//    book.setBname(bname);
//    book.setPrice(Float.valueOf(price));
//    System.out.println("bookAction.add..5");
    request.setAttribute("content", "你好");
//    response.sendRedirect("res.jsp");
    return "toList";
    }
  public String del(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("bookAction.del..5");
    request.setAttribute("content", "你好");
//    response.sendRedirect("res.jsp");
    return "toList";
    }
  public String upd(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("bookAction.upd..5");
    request.setAttribute("content", "你好");
//    response.sendRedirect("res.jsp");
    return "toList";
    }
  public String list(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    System.out.println("bookAction.list..");
    request.setAttribute("content", "你好");
//    request.getRequestDispatcher("res.jsp").forward(request, response);
    return "list";  
  }
  @Override
  public Book getMondel() {
    // TODO Auto-generated method stub
    return book;
  }
}
package com.zhulinjun.entity;
public class Book {
private int bid;
private String bname;
private float price;
public int getBid() {
  return bid;
}
public void setBid(int bid) {
  this.bid = bid;
}
public String getBname() {
  return bname;
}
public void setBname(String bname) {
  this.bname = bname;
}
public float getPrice() {
  return price;
}
public void setPrice(float price) {
  this.price = price;
}
@Override
public String toString() {
  return "Book [bid=" + bid + ", bname=" + bname + ", price=" + price + "]";
}
public Book(int bid, String bname, float price) {
  super();
  this.bid = bid;
  this.bname = bname;
  this.price = price;
}
public Book() {
  super();
  // TODO Auto-generated constructor stub
}
}
package com.zhulinjun.model;
/**
 * 模型驱动接口
 * Book book=new Book():
 * @author 朱
 *
 * @param <T>
 */
public interface MondelDriver<T> {
  T getMondel();
}
package com.zhulinjun.framework;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletConfig;
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 org.apache.commons.beanutils.BeanUtils;
import org.dom4j.DocumentException;
import com.zhulinjun.entity.Book;
import com.zhulinjun.model.ActionModel;
import com.zhulinjun.model.ConfigModel;
import com.zhulinjun.model.ConfigModelFactory;
import com.zhulinjun.model.ForwardModel;
import com.zhulinjun.model.MondelDriver;
@WebServlet("*.action")
public class DispatcherServlet extends HttpServlet implements MondelDriver<Book>{
Book book=new Book();
  public Map<String, Action> actionMap = new HashMap<String, Action>();
  // 以前所有的子控制器是放到map集合中，现在所有的子控制器在mvc.xml中，其实就是放到configModel
  private ConfigModel configModel;
  @Override
  public void init(ServletConfig config) throws ServletException {
    // actionMap.put("/book", new bookAction());
    // actionMap.put("/order", new orderAction());
      try {
        configModel=ConfigModelFactory.build();
      } catch (Exception e) {
        e.printStackTrace();
      }
    super.init(config);
  }
  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    this.doPost(request, response);
  }
  @Override
  protected void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    // http://locahost:80/mvc/book.action?methodName=add
    String uri = request.getRequestURI();
//    System.out.println(uri);
    uri = uri.substring(uri.lastIndexOf("/"), uri.lastIndexOf("."));
//    System.out.println("url" + uri);
    // Action action = actionMap.get(uri);
    // 通过uri=/book，在configModel对象中找
    ActionModel actionMondel = configModel.pop(uri);
//    System.out.println(actionMondel + "" + "actionMondel");
    if (actionMondel == null)
      throw new RuntimeException("action not config");
    // com.zking.web.BookAction
    String type = actionMondel.getType();
    // BookAction bookaction=new BookAction();
    Action action;
    try {
      action = (Action) Class.forName(type).newInstance();
//      bookaction有没有实现MondelDriver接口
      if(action instanceof MondelDriver) {
        MondelDriver md=(MondelDriver) action;
        Object bean = md.getMondel();
        Map<String, String[]> map = request.getParameterMap();
//         3.将参数值封装到对应的对象中
        BeanUtils.populate(bean, request.getParameterMap());
      }     
//      具体业务代码执行后的返回值 add/upd/del/list的返回值j==>list/tolist
      String res = action.execute(request, response);
//            要通过返回值拿到，该方法结果是重定向还是转发，还是跳转哪个页面
      ForwardModel forwardModel = actionMondel.pop(res);
      if(forwardModel!=null){
        boolean redirect=forwardModel.isRedirect();
        String path=forwardModel.getPath();
        if(redirect) {
          response.sendRedirect(request.getContextPath() + "/" + path);
        }else {
          request.getRequestDispatcher(path).forward(request, response);
        }
      }
    } catch (Exception e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
  }
  @Override
  public Book getMondel() {
    // TODO Auto-generated method stub
    return book;
  }
}
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前端开发 程序员 API
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存储 开发框架 前端开发
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前端开发 程序员 设计模式
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