一个简单的MVC框架的实现-基于注解的实现

Posted 2020-06-16

1、@Action注解声明 

package com.togogo.webtoservice.annotations;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Target(value=ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Action {
    // String namespace() default "";
}

 

2、@Path注解声明 

package com.togogo.webtoservice.annotations;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * 如果放在类上面，表示名命空间
 * 如果放在方法上面，表示路径
 * @author Administrator
 *
 */
@Target(value={ElementType.TYPE,ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Path {
    
    String value();

}

 

3、ActionExecute类

package com.togogo.webtoservice;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.togogo.webtoservice.annotations.Action;
import com.togogo.webtoservice.annotations.Path;

/**
 * 必须的问题 1、判断传进来的类的对象是不是一个Action 2、通过url，直接调用于Action的方法 3、返回转路径
 * 
 * @author Administrator
 *
 */
public class ActionExecute {
    private Object action;
    private Class<? extends Object> actionClass;
    private HttpServletRequest request;
    private HttpServletResponse response;

    ActionExecute(Object o, HttpServletRequest request,
            HttpServletResponse response) {
        this.action = o;
        this.actionClass = this.action.getClass();
        this.request = request;
        this.response = response;
    }

    /**
     * 获得命名空间
     * 
     * @return
     */
    private String getNamespace() {
        Path pathAnnotation = actionClass.getAnnotation(Path.class);
        if (pathAnnotation != null) {
            return pathAnnotation.value();
        } else {
            return null;
        }
    }

    /**
     * 判断是否是一个Action
     * 
     * @return
     */
    private boolean isAction() {
        Action actionAnnotation = actionClass.getAnnotation(Action.class);
        if (actionAnnotation == null) {
            return false;
        } else {
            return true;
        }
    }

    /**
     * 获得方法
     * 
     * @return
     */
    private Method getMethod() {
        String uri = request.getRequestURI();

        Method[] methods = actionClass.getDeclaredMethods();
        for (int i = 0; i < methods.length; i++) {
            Method m = methods[i];
            Path path = m.getAnnotation(Path.class);
            if (this.getNamespace() != null) {
                if (uri.contains(this.getNamespace())) {
                    if (path != null) {
                        if (uri.contains(path.value())) {
                            return m;
                        }
                    }
                }else{
                    System.out.println("--命名空间不匹配--");
                    return null;
                }

            } else {
                if (path != null) {
                    if (uri.contains(path.value())) {
                        return m;
                    }
                }
            }
        }
        return null;
    }

    String execute() throws IllegalAccessException, IllegalArgumentException,
            InvocationTargetException {
        if (isAction()) {
            Method method = this.getMethod();
            String rePath = (String) method.invoke(action, request, response);
            return rePath;
        } else {
            System.out.println("--这不是一个Action--");
            return null;
        }
    }

}

 

4、核心控制器

package com.togogo.webtoservice;

import java.io.IOException;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class DispacherServlet extends HttpServlet {
    private static String config=null;
    private static String enconding="UTF-8";

    @Override
    public void init(ServletConfig config) throws ServletException {
        String initConfig=config.getInitParameter("config");
        String initEnconding=config.getInitParameter("enconding");
        if(initConfig!=null){
            DispacherServlet.config=initConfig;
        }
        //通过web描述符文件web.xml配置
        if(initEnconding!=null){
            DispacherServlet.enconding=initEnconding;
        }
        
        super.init(config);
    }

    /**
     * 接收任何请求,
     */
    @Override
    protected void service(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        try {
            request.setCharacterEncoding(enconding);
            response.setCharacterEncoding(enconding);
            String uri = request.getRequestURI();
            StringBuilder sb = new StringBuilder(uri);
            String path = sb.substring(uri.lastIndexOf("/") + 1,
                    uri.lastIndexOf("!"));
            System.out.println(path);
            String className = Config.getClassName(path,config);
            Object action = ActionFactory.create(className);
            ActionExecute actionExecute =new ActionExecute(action,request, response);
            String result = actionExecute.execute();
            
            if (result.contains(":")) {
                StringBuilder resultStr = new StringBuilder(result);
                String rePath=resultStr.substring(result.indexOf(":")+1, result.length());
                if(result.contains("redirect:")){
                    response.sendRedirect(rePath);
                }else if(result.contains("forward:")){
                    request.getRequestDispatcher(rePath).forward(request, response);
                }
                
            } else {
                request.getRequestDispatcher(result).forward(request, response);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

}

 

5、Action对象工厂

package com.togogo.webtoservice;


/**
 * 一个创建Action的工厂
 * @author Administrator
 *
 */
public class ActionFactory {
    
    public static Object create(String className){
        Object action=null;
        try {
            action = (Object)Class.forName(className).newInstance();
        } catch (InstantiationException e) {
            
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            
            e.printStackTrace();
        } catch (ClassNotFoundException e) {

            e.printStackTrace();
        }
        return action;
    }

}

 

6、配置文件类

package com.togogo.webtoservice;

import java.util.HashMap;
import java.util.Map;
import java.util.ResourceBundle;

/**
 * 路径与类名映身
 * 
 * @author Administrator
 *
 */
public class Config {
    // private static Map<String, String> classNames = new HashMap<String,
    // String>();

    /**
     * 通过key
     * 
     * @param key
     * @return
     */
    public static String getClassName(String key, String config) {
        ResourceBundle bundle = null;
        if (config == null||"".equals(config)) {
            bundle = ResourceBundle.getBundle("Action");
        } else {
            bundle = ResourceBundle.getBundle(config);
        }
        return bundle.getString(key);
    }


}

 

--------------------------------------------------------测试框架------------------------------------------------

7、UserAction类

package com.togogo.action;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.togogo.webtoservice.annotations.Action;
import com.togogo.webtoservice.annotations.Path;

@Action
public class UserAction {


    /**
     * 用户登录
     * 
     * @param request
     * @param response
     * @return
     */
    @Path(value="login.do")
    public String login(HttpServletRequest request, HttpServletResponse response) {
        System.out.println("我在登录");
        System.out.println("我在登录.");
        System.out.println("我在登录..");
        System.out.println("我在登录.");
        System.out.println("我在登录..");
        System.out.println("我在登录.");
        System.out.println("我在登录..");
        System.out.println("我在------登录..");
        System.out.println("我在------登录..");
        System.out.println("我在------登录..");
        System.out.println("我在------登录..");
        return "main.jsp";
    }

    /**
     * 用户注册
     * 
     * @param request
     * @param response
     * @return
     */
    @Path(value="register.do")
    public String register(HttpServletRequest request,
            HttpServletResponse response) {
        System.out.println("我在注册");
        return "forward:main.jsp";
    }
    
    /**
     * 用户注册
     * 
     * @param request
     * @param response
     * @return
     */
    public String undo(HttpServletRequest request,
            HttpServletResponse response) {
        System.out.println("我在撤消");
        return "redirect:main.jsp";
    }

}

 

8、映射配置文件Action.properties

user=com.togogo.action.UserAction

 

9、web.xml配置

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/javaee"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    id="WebApp_ID" version="3.0">
    <display-name>web_mvc_webtoservice</display-name>
   <!-- 这是一个核心控制器 -->
    <servlet>
        <servlet-name>dispacherServlet</servlet-name>
        <servlet-class>com.togogo.webtoservice.DispacherServlet</servlet-class>
        <init-param>
          <param-name>config</param-name>
          <param-value>resources.Action</param-value>
        </init-param>
    </servlet>

    <servlet-mapping>
        <servlet-name>dispacherServlet</servlet-name>
        <url-pattern>*.do</url-pattern>
    </servlet-mapping>
    
    <welcome-file-list>
        <welcome-file>default.jsp</welcome-file>
    </welcome-file-list>
</web-app>

 

10、测试页面

<%@ 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></a>
  <form action="${pageContext.request.contextPath }/user!login.do" method="post">
<!--      <input name="clasName" value="com.togogo.action.UserAction"> -->
     <input type="submit">
  
  </form>
</body>
</html>

　　

源码下载：

 http://files.cnblogs.com/files/zhuyuejiu/web_mvc_webtoservice_annotation.zip