Servlet容器中放着我们所有要访问的Servlet，根据我们具体的请求来访问不同的Servlet。下面是一个简单的Servlet容器的实现。request和response的封装以及连接器的实现代码这里就不再重复写了，请看上一篇博客。

servlet

package com.hcserver.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

public class MyServlet extends HttpServlet{

private static final long serialVersionUID = 1L;

@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 {

String aa = req.getParameter("aa");

String bb = req.getParameter("bb");

System.out.println("param aa = "+aa);

System.out.println("param bb = "+bb);

resp.getWriter().print("hello world...");

}

}

servlet容器

package com.hcserver.container;

import java.io.File;

import java.util.HashMap;

import java.util.Map;

import javax.servlet.http.HttpServlet;

public class Container {

public final static String WEB_ROOT = Container.class.getResource("/webapps").getPath();

private Map> projectMap = new HashMap<>();

private static Container container = new Container();

private Container(){}

public static Container getInstance(){

return container;

}

public void init(){

try{

//模拟解析web.xml，利用反射得到servlet实例

Map map = new HashMap<>();

Class> servletClass = Class.forName("com.hcserver.servlet.MyServlet");

HttpServlet newInstance = (HttpServlet)servletClass.getConstructor(new Class[]{}).newInstance(new Object[]{});

map.put("myServlet", newInstance);

projectMap.put("hello",map);

}catch(Exception e){

}

}

public Map getProject(String projectName){

return projectMap.get(projectName);

}

public static void main(String[] args) {

container.init();

}

}

处理器修改

package com.hcserver.process;

import java.util.Map;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.hcserver.container.Container;

public class Process {

public void service(HttpServletRequest request,HttpServletResponse response){

String project = request.getContextPath();

String servletPath = request.getServletPath();

//得到容器类

Container container = Container.getInstance();

Map servletMap = container.getProject(project);

HttpServlet servlet = servletMap.get(servletPath);

try {

//返回页面

servlet.service(request, response);

} catch (Exception e) {

e.printStackTrace();

}

}

}

后台输出

param aa = 1

param bb = 3