tomcat06-手写简化tomcat(Bio)

前言

前面的文章，其实我们说过了。。回忆下
tomcat官网：https://tomcat.apache.org

The Apache Tomcat® software is an open source implementation of the Java Servlet, 
JavaServer Pages, Java Expression Language and Java WebSocket technologies.

Tomcat 是使用了Java WebSocket技术和serlet技术，tomcat使用java实现

最核心的两部分connector和container
connector部分，我们用bio的方式，websocket实现
container部分，用servlet集成
我们一步一步的说明

只实现web容器

新建一个maven项目叫my-tomcat

package com.my.tomcat.bio;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Properties;


public class Tomcat {
    private static Logger logger= LoggerFactory.getLogger(Tomcat.class);
    private static Properties pro = new Properties();

    
    public static void init(){
        try {
            FileInputStream fileInputStream = new FileInputStream("src/main/resources/server.properties");
            pro.load(fileInputStream);
            logger.info("init 读取配置完成");
        } catch (FileNotFoundException e) {
            logger.error("初始化server配置文件错误",e.getMessage());
            e.printStackTrace();
        } catch (IOException e) {
            logger.error("pro加载server报错",e.getMessage());
            e.printStackTrace();
        }
    }

    
    public static void start (){
        //启动web容器
        int port = Integer.parseInt(pro.getProperty("server.port"));
        ServerSocket serverSocket = null;

        try {
            serverSocket = new ServerSocket(port);
            while (true){
                Socket accept = serverSocket.accept();
                logger.info("收到连接请求.....");

                OutputStream outputStream=accept.getOutputStream();
                InputStream inputStream = accept.getInputStream();

                //先不使用servlet容器
                //处理输入
                dealInputStream(inputStream);
                //处理输出
                dealOutStream(outputStream,"success request");
            }
        } catch (IOException e) {
            logger.error("启动tomcat报错",e.getMessage());
            e.printStackTrace();
        }finally {
            if(null !=serverSocket)
            {
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    
    private static void dealInputStream(InputStream inputStream) throws IOException {
        String  httStr = "";
        byte [] contentByte = new byte[1024];
        int length;
        if ((length = inputStream.read(contentByte)) >0){
            httStr = new String(contentByte,0,length);
        }
        logger.info("访问请求内容为："+httStr);

    }

    
    private static void dealOutStream(OutputStream outputStream, String outContent) throws IOException {
        String httpResponse =
                "HTTP/1.1 200 OKn" +
                        "Content-Type: text/htmln" +
                        "rn" + outContent;
        outputStream.write(httpResponse.getBytes());
        outputStream.close();
    }

    
    public static void main(String[] args) {
        init();
        start();
    }


}

pom.xml文件



    4.0.0

    org.example
    my-tomcat
    1.0-SNAPSHOT

    
        1.11
        UTF-8
    


    
        
            org.slf4j
            slf4j-api
            1.5.6
        
        
            ch.qos.logback
            logback-classic
            1.2.3
        

    

    
        
            
                maven-compiler-plugin
                
                    ${java.version}
                    ${java.version}
                    ${build.sourceEncoding}

• Server.properties

server.port=8080

• 使用main方法启动

14:38:57.040 [main] INFO com.my.tomcat.bio.Tomcat - init 读取配置完成

• 结果

访问：http://localhost:8080/mytomcat?id=10
看看控制台打印：

14:45:15.590 [main] INFO com.my.tomcat.bio.Tomcat - 收到连接请求.....
14:45:15.612 [main] INFO com.my.tomcat.bio.Tomcat - 访问请求内容为：GET /mytomcat?id=10 HTTP/1.1
Host: localhost:8080
Connection: keep-alive
Cache-Control: max-age=0
sec-ch-ua: " Not A;Brand";v="99", "Chromium";v="100", "Google Chrome";v="100"
sec-ch-ua-mobile: ?0
sec-ch-ua-platform: "Windows"
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.60 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*
public class ServletMappingConfig {
    public static List servletMappingList = new ArrayList<>();
    public static Logger logger = LoggerFactory.getLogger(ServletMappingConfig.class);

    public static void initServletMapping(Properties prop) {
        Set strings = prop.stringPropertyNames();
        for (String str : strings) {
            if (str.endsWith(".url")) {
                String servletName = str.replaceAll(".url", "");
                String value[] = prop.getProperty(str).split(":");
                if (null == value || value.length != 2) {
                    logger.error("servlet配置异常--key=" + str + "--value=" + prop.getProperty(str));
                    logger.error("servlet请参考模板格式：servletName.url = ClassName:url");
                    continue;
                }
                ServletMapping servletInfo = new ServletMapping(servletName, value[0], value[1]);
                logger.info("初始化servlet:" + servletInfo.toString());
                servletMappingList.add(servletInfo);
            }
        }
    }
}

package com.my.tomcat.bio.servlet;


public class ServletMapping {
    private String servletName;
    private String clazz;
    private String url;

    public ServletMapping(String servletName, String clazz, String url) {
        this.servletName = servletName;
        this.clazz = clazz;
        this.url = url;
    }

    @Override
    public String toString() {
        return "ServletMapping{" +
                "servletName='" + servletName + ''' +
                ", clazz='" + clazz + ''' +
                ", url='" + url + ''' +
                '}';
    }

    public String getServletName() {
        return servletName;
    }

    public void setServletName(String servletName) {
        this.servletName = servletName;
    }

    public String getClazz() {
        return clazz;
    }

    public void setClazz(String clazz) {
        this.clazz = clazz;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }
}

• init方法中servlet配置文件初始化并解析，结果放入内存中

这个在Tomcat类中，最后再看

• start方法中的类

package com.my.tomcat.bio.servlet;

public abstract class Servlet {

    public static  final  String GET="GET";
    public static  final  String PUT="POST";
    public abstract  void doGet(HttpServletRequest request, HttpServletResponse response);

    public abstract  void doPost(HttpServletRequest request, HttpServletResponse response);

    public void service(HttpServletRequest request, HttpServletResponse response)
    {
        if(request == null)
        {
            System.out.println("HttpServletRequest is null");
        }
        if(response == null)
        {
            System.out.println("HttpServletResponse is null");
        }
        if(request.getMethod().equals("GET"))
        {
            doGet(request,response);
        }else if(request.getMethod().equals("POST"))
        {
            doPost(request,response);
        }


    }


}

package com.my.tomcat.bio.servlet;

import com.my.tomcat.bio.Tomcat;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.io.InputStream;


public class HttpServletRequest  {
    private static Logger logger= LoggerFactory.getLogger(HttpServletRequest.class);
    private  String url;
    private  String method;

    public HttpServletRequest(InputStream inputStream)throws IOException
    {
        String  httStr = "";
        byte [] contentByte = new byte[1024];
        int length;
        if ((length = inputStream.read(contentByte)) >0){
            httStr = new String(contentByte,0,length);
        }
        logger.info("servlet访问请求内容为："+httStr);
      
	if (!httStr.isEmpty() && !httStr.equals("")) {
	            String httpHead = httStr.split("n")[0];
	            method = httpHead.split("\s")[0];
	            url = httpHead.split("\s")[1];
	        }
	    }
    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public String getMethod() {
        return method;
    }

    public void setMethod(String method) {
        this.method = method;
    }
}

package com.my.tomcat.bio.servlet;

import java.io.IOException;
import java.io.OutputStream;


public class HttpServletResponse {
    private OutputStream outputStream;
    public HttpServletResponse(OutputStream outputStream)
    {
        this.outputStream=outputStream;
    }

    public void write(String content) throws IOException {
        String httpResponse =
                "HTTP/1.1 200 OKn" +
                        "Content-Type: text/htmln" +
                        "servlet响应"+
                        "rn" + content;
        outputStream.write(httpResponse.getBytes());
        outputStream.close();
    }
}

• 请求controller servlet的类

package com.my.tomcat.bio.servlet.controller;

import com.my.tomcat.bio.servlet.HttpServletRequest;
import com.my.tomcat.bio.servlet.HttpServletResponse;
import com.my.tomcat.bio.servlet.Servlet;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;


public class LoginServlet extends Servlet {
    public static Logger logger = LoggerFactory.getLogger(LoginServlet.class);

    @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response) {
        logger.info("get method Login Servlet");
        try {
            response.write("login success");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void doPost(HttpServletRequest request, HttpServletResponse response) {
        logger.info("post method Login Servlet");
        try {
            response.write("login success");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

package com.my.tomcat.bio.servlet.controller;

import com.my.tomcat.bio.servlet.HttpServletRequest;
import com.my.tomcat.bio.servlet.HttpServletResponse;
import com.my.tomcat.bio.servlet.Servlet;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;


public class HelloServlet extends Servlet {

    public static Logger logger = LoggerFactory.getLogger(LoginServlet.class);

    @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response) {
        logger.info("get method Hello Servlet");
        try {
            response.write("Hello success");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void doPost(HttpServletRequest request, HttpServletResponse response) {
        logger.info("post method Hello Servlet");
        try {
            response.write("Hello success");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

• tomcatBio主启动类

package com.my.tomcat.bio;

import com.my.tomcat.bio.servlet.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Map;
import java.util.Properties;
import java.util.concurrent.ConcurrentHashMap;


public class TomcatBio {
    private static Logger logger = LoggerFactory.getLogger(TomcatBio.class);
    private static Properties pro = new Properties();

    //servlet接口请求池
    private static Map servletPool = new ConcurrentHashMap<>();

    
    public static void init() {
        try {
            FileInputStream fileInputStream = new FileInputStream("src/main/resources/server.properties");
            pro.load(fileInputStream);
            logger.info("init 读取配置完成");

            //初始化servlet配置
            ServletMappingConfig.initServletMapping(pro);
            //解析servlet配置,并放入请求池中
            for (ServletMapping servletMapping : ServletMappingConfig.servletMappingList) {
                servletPool.put(servletMapping.getUrl(), servletMapping.getClazz());
            }
            logger.info("init servlet 配置完成");
        } catch (FileNotFoundException e) {
            logger.error("初始化server配置文件错误", e.getMessage());
            e.printStackTrace();
        } catch (IOException e) {
            logger.error("pro加载server报错", e.getMessage());
            e.printStackTrace();
        }
    }

    
    public static void start() {
        //启动web容器
        int port = Integer.parseInt(pro.getProperty("server.port"));
        ServerSocket serverSocket = null;

        try {
            serverSocket = new ServerSocket(port);
            while (true) {
                Socket accept = serverSocket.accept();
                logger.info("收到连接请求.....");

                OutputStream outputStream = accept.getOutputStream();
                InputStream inputStream = accept.getInputStream();

               
                //使用servlet容器
                HttpServletRequest httpServletRequest = new HttpServletRequest(inputStream);
                HttpServletResponse httpServletResponse = new HttpServletResponse(outputStream);
                dispatch(httpServletRequest,httpServletResponse);
                logger.info("servlet请求完成.....");
            }
        } catch (IOException e) {
            logger.error("启动tomcat报错", e.getMessage());
            e.printStackTrace();
        } finally {
            if (null != serverSocket) {
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    
    private static void dealInputStream(InputStream inputStream) throws IOException {
        String httStr = "";
        byte[] contentByte = new byte[1024];
        int length;
        if ((length = inputStream.read(contentByte)) > 0) {
            httStr = new String(contentByte, 0, length);
        }
        logger.info("访问请求内容为：" + httStr);

    }

    
    private static void dealOutStream(OutputStream outputStream, String outContent) throws IOException {
        String httpResponse =
                "HTTP/1.1 200 OKn" +
                        "Content-Type: text/htmln" +
                        "rn" + outContent;
        outputStream.write(httpResponse.getBytes());
        outputStream.close();
    }

    
    public static void dispatch(HttpServletRequest request, HttpServletResponse response) {
        if (!servletPool.containsKey(request.getUrl())) {
            logger.error("servlet分发器未找到对应的servlet的配置");
            try {
                String httpResponse =
                        "HTTP/1.1 200 OKn" +
                                "Content-Type: text/htmln" +
                                "rn" + "404 Exception";
                response.write(httpResponse);
                return;
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        String className = servletPool.get(request.getUrl());
        try {
            Class clazz = (Class) Class.forName(className);
            Servlet servlet = clazz.newInstance();
            servlet.service(request, response);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        }
    }


    
    public static void main(String[] args) {
        init();
        start();
    }


}

验证

启动TomcatBio.java–>main()

17:45:27.718 [main] INFO com.my.tomcat.bio.TomcatBio - init 读取配置完成
17:45:27.774 [main] INFO com.my.tomcat.bio.servlet.ServletMappingConfig - 初始化servlet:ServletMapping{servletName='helloServlet', clazz='com.my.tomcat.bio.servlet.controller.HelloServlet', url='/hello'}
17:45:27.774 [main] INFO com.my.tomcat.bio.servlet.ServletMappingConfig - 初始化servlet:ServletMapping{servletName='loginServlet', clazz='com.my.tomcat.bio.servlet.controller.LoginServlet', url='/login'}
17:45:27.774 [main] INFO com.my.tomcat.bio.TomcatBio - init servlet 配置完成

访问：http://localhost:8080/mytomcat?id=10
结果：

访问：http://localhost:8080/login
http://localhost:8080/hello

17:57:07.546 [main] INFO com.my.tomcat.bio.servlet.controller.LoginServlet - get method Login Servlet
17:57:07.548 [main] INFO com.my.tomcat.bio.TomcatBio - servlet请求完成.....
17:57:07.548 [main] INFO com.my.tomcat.bio.TomcatBio - 收到连接请求.....


17:57:12.447 [main] INFO com.my.tomcat.bio.servlet.controller.LoginServlet - get method Hello Servlet
17:57:12.448 [main] INFO com.my.tomcat.bio.TomcatBio - servlet请求完成.....

tomcat06-手写简化tomcat(Bio)

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