package com.hongyuan.route;
 
import java.io.File;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
 
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
 
public class WebFilter implements Filter {
 
    public static final String BASE_PACKAGE="com.hongyuan";
    public static final String CLASS_FLAG="Action";
    @Override
    public void destroy() {}
 
    @Override
    public void doFilter(ServletRequest request, ServletResponse response,FilterChain chain) throws IOException, ServletException {
         
        if(!hasResouce(request)){
             
            String requestPath=((HttpServletRequest)request).getServletPath();
            if(requestPath.indexOf(".")>=0){
                requestPath=requestPath.substring(0, requestPath.indexOf("."));
            }
            if(requestPath.endsWith("/")){
                requestPath=requestPath.substring(0, requestPath.length()-1);
            }
            //获取请求的类全限定名
            String className=BASE_PACKAGE+requestPath.replaceAll("/", ".")+CLASS_FLAG;
            //获取请求方法名称
            String methodName=request.getParameter("method");
            if(methodName==null||"".equals(methodName.trim())){
                methodName="index";
            }
            try {
                //获取处理类并响应请求
                Class clazz=Class.forName(className);
                Object instance=this.initContext(clazz,request,response);
                Method method=clazz.getMethod(methodName, new Class[]{});
                Object result=method.invoke(instance, new Object[]{});
                response.getWriter().print(result);
            } catch (Exception e) {
                e.printStackTrace(response.getWriter());
            }
        }else{
            chain.doFilter(request, response);
        }
 
    }
    //判断是否存在请求的资源
    private boolean hasResouce(ServletRequest request) {
        String realPath=request.getServletContext().getRealPath(((HttpServletRequest)request).getServletPath());
        File resouce=new File(realPath);
        if(resouce.exists()){
            return true;
        }else{
            return false;
        }
    }
    //初始化上下文
    private Object initContext(Class clazz, ServletRequest request,
            ServletResponse response) throws Exception{
        Object instance=clazz.newInstance();
        clazz.getMethod("setRequest",new Class[]{ServletRequest.class}).invoke(instance, new Object[]{request});
        clazz.getMethod("setResponse", new Class[]{ServletResponse.class}).invoke(instance, new Object[]{response});
        return instance;
    }
 
    @Override
    public void init(FilterConfig arg0) throws ServletException {}
 
}

package com.hongyuan.route;
 
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
 
public abstract class BaseAction {
    protected ServletRequest request=null;
    protected ServletResponse response=null;
     
    public ServletRequest getRequest() {
        return request;
    }
    public void setRequest(ServletRequest request) {
        this.request = request;
    }
    public ServletResponse getResponse() {
        return response;
    }
    public void setResponse(ServletResponse response) {
        this.response = response;
    }
     
}