目录
1. http协议
CS架构
建立连接“三次握手” 断开连接 “四次挥手”
三次握手：
client：可以与你建立连接吗？
server：可以的
client: 我也可以了
四次挥手：
client：我要断开
server：可以断开
server：我要断开
client：可以断开
双方都有一个确认 断开的过程 因为连接的建立 双方都有资源打开 都有port号被占用 双方需要将打开的资源关闭掉
请求的格式：
响应的格式：
2. 自定义的web框架
核心：Request Response类
applet
servlet
3. 具体实现
Request Response
package com.msb.mytomcat;
import java.io.IOException;
import java.io.InputStream;
/**
* @Auther: jack.chen
* @Date: 2023/10/15 - 10 - 15 - 9:24
* @Description: com.msb.mytomcat
* @version: 1.0
*/
public class Request {
//请求方法 GET POST PUT DELETE ...
private String requestMethod;
// 请求的url
private String requestUrl;
// 构造方法 将请求的inputStream 转化成Request对象
public Request(InputStream inputStream) throws IOException {
byte[] buffer = new byte[1024];
int len = 0;// 每次读取的长度
String str = null;
if ((len=inputStream.read(buffer))>0){
str = new String(buffer, 0, len);
}
// GET / HTTP/1.1
String data = str.split("\r\n")[0];
String[] params = data.split(" ");
this.requestMethod = params[0];
this.requestUrl = params[1];
}
public String getRequestMethod() {
return requestMethod;
}
public void setRequestMethod(String requestMethod) {
this.requestMethod = requestMethod;
}
public String getRequestUrl() {
return requestUrl;
}
public void setRequestUrl(String requestUrl) {
this.requestUrl = requestUrl;
}
@Override
public String toString() {
return "Request{" +
"requestMethod='" + requestMethod + '\'' +
", requestUrl='" + requestUrl + '\'' +
'}';
}
}
package com.msb.mytomcat;
import java.io.IOException;
import java.io.OutputStream;
/**
* @Auther: jack.chen
* @Date: 2023/10/15 - 10 - 15 - 9:24
* @Description: com.msb.mytomcat
* @version: 1.0
*/
public class Response {
private OutputStream outputStream;
public Response(OutputStream outputStream) {
this.outputStream = outputStream;
}
// 将返回的str 包装成前端能识别的 响应
public void write(String str) throws IOException {
StringBuilder builder = new StringBuilder();
builder.append("HTTP/1.1 200 OK\n")
.append("Content-Type:text/html\n")
.append("\r\n")
.append("<html>")
.append("<body>")
.append("<h1>"+str+"</h1>")
.append("</body>")
.append("</html>");
this.outputStream.write(builder.toString().getBytes());
this.outputStream.flush();
this.outputStream.close();
}
}
maping
package com.msb.mytomcat;
import java.util.HashMap;
/**
* @Auther: jack.chen
* @Date: 2023/10/15 - 10 - 15 - 10:06
* @Description: com.msb.mytomcat
* @version: 1.0
*/
// 请求utl 与 处理类servlet 映射关系
public class Mapping {
public static HashMap<String, String> map = new HashMap<>();
static {
map.put("/mytomcat", "com.msb.mytomcat.Servlet");
}
public HashMap<String, String> getMap(){
return map;
}
}
抽象类HttpServlet
package com.msb.mytomcat;
import java.io.IOException;
/**
* @Auther: jack.chen
* @Date: 2023/10/15 - 10 - 15 - 10:10
* @Description: com.msb.mytomcat
* @version: 1.0
* 抽象类
*/
public abstract class HttpServlet {
public static final String METHOD_GET = "GET";
public static final String METHOD_POST = "POST";
public abstract void doGet(Request request, Response response) throws IOException;
public abstract void doPost(Request request, Response response) throws IOException;
// 根据请求的方式 调用对应的方法
public void service(Request request, Response response) throws IOException {
if (METHOD_GET.equals(request.getRequestMethod())){
doGet(request, response);
} else if (METHOD_POST.equals(request.getRequestMethod())){
doPost(request, response);
}
}
}
实现类Servlet
package com.msb.mytomcat;
import java.io.IOException;
/**
* @Auther: jack.chen
* @Date: 2023/10/15 - 10 - 15 - 10:23
* @Description: com.msb.mytomcat
* @version: 1.0
*/
public class Servlet extends HttpServlet{
@Override
public void doGet(Request request, Response response) throws IOException {
response.write("get method !");
}
@Override
public void doPost(Request request, Response response) throws IOException {
response.write("post method !");
}
}
服务端：
package com.msb.mytomcat;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
/**
* @Auther: jack.chen
* @Date: 2023/10/15 - 10 - 15 - 10:26
* @Description: com.msb.mytomcat
* @version: 1.0
* 服务端
*/
public class Server {
public static void startServer(int port) throws IOException, ClassNotFoundException, IllegalAccessException, InstantiationException {
ServerSocket serverSocket = new ServerSocket(port);
Socket socket = null;
while (true){
socket = serverSocket.accept();
// input output
InputStream inputStream = socket.getInputStream();
OutputStream outputStream = socket.getOutputStream();
Request request = new Request(inputStream);
Response response = new Response(outputStream);
String url = request.getRequestUrl();
String clazz = new Mapping().getMap().get(url);// 处理类的包
if(clazz!=null){
Class<Servlet> servletClass = (Class<Servlet>) Class.forName(clazz);
Servlet servlet = servletClass.newInstance();
servlet.service(request, response);
System.out.println("200 ok "+ request.toString());
}
}
}
public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException, IOException {
startServer(8080);
}
}
4. 启动
