这是我简单的web服务器，在JMeter中用于测试webhook(这就是为什么它会在收到请求后关闭并结束自己)。

import java.io.IOException;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class HttpServer {

    private static int extractContentLength(StringBuilder sb) {
        int length = 0;
        String[] lines = sb.toString().split("\\n");
        for (int i = 0; i < lines.length; i++) {
            String s = lines[i];
            if (s.toLowerCase().startsWith("Content-Length:".toLowerCase()) && i <= lines.length - 2) {
                String slength = s.substring(s.indexOf(":") + 1, s.length()).trim();
                length = Integer.parseInt(slength);
                System.out.println("Length = " + length);
                return length;
            }
        }
        return 0;
    }

    public static void main(String[] args) throws IOException {
        
        
        int port = Integer.parseInt(args[0]);
        System.out.println("starting HTTP Server on port " + port);

        StringBuilder outputString = new StringBuilder(1000);

        ServerSocket serverSocket = new ServerSocket(port);
        serverSocket.setSoTimeout(3 * 60 * 1000); // 3 minutes timeout
        while (true) {

            outputString.setLength(0); // reset buff

            Socket clientSocket = serverSocket.accept(); // blocking
            PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);

            try {

                boolean isBodyRead = false;
                int dataBuffer;
                while ((dataBuffer = clientSocket.getInputStream().read()) != -1) {

                    if (dataBuffer == 13) { // CR
                        if (clientSocket.getInputStream().read() == 10) { // LF
                            outputString.append("\n");
                        }
                    } else {
                        outputString.append((char) dataBuffer);
                    }
                    
                    // do we have Content length
                    int len = extractContentLength(outputString);
                    if (len > 0) {
                        int actualLength = len - 1; // we need to substract \r\n
                        for (int i = 0; i < actualLength; i++) {
                            int body = clientSocket.getInputStream().read();
                            outputString.append((char) body);
                        }
                        isBodyRead = true;
                        break;
                    }

                } // end of reading while

                if (isBodyRead) {
                    // response headers
                    out.println("HTTP/1.1 200 OK");
                    out.println("Connection: close");
                    out.println(); // must have empty line for HTTP
                    
                    out.flush(); 
                    out.close(); // close clients connection
                }

            } catch (IOException ioEx) {
                System.out.println(ioEx.getMessage());
            }

            System.out.println(outputString.toString());
            break; // stop server - break while true
            
        } // end of outer while true
        
        serverSocket.close();

    } // end of method

}

你可以这样测试:

curl -X POST -H "Content-Type: application/json" -H "Connection: close" -d '{"name": "gustinmi", "email": "gustinmi at google dot com "}' -v http://localhost:8081/

我玩得很开心，我玩转了一下，拼凑出了这个。我希望这对你有所帮助。 你需要安装Gradle或者使用Maven插件。

build.gradle

plugins {
    id 'application'
}

group 'foo.bar'
version '1.0'

repositories {
    mavenCentral()
}

application{
    mainClass.set("foo.FooServer")
}

dependencies {}

FooServer 主入口点，你的主类。

package foo;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.nio.ByteBuffer;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class FooServer {

    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = new ServerSocket(7654);
        serverSocket.setPerformancePreferences(0, 1, 2);

        /* the higher the numbers, the better the concurrent performance, ha!
           we found that a 3:7 ratio to be optimal
           3 partitioned executors to 7 network executors */

        ExecutorService executors = Executors.newFixedThreadPool(3);
        executors.execute(new PartitionedExecutor(serverSocket));
    }


    public static class PartitionedExecutor implements Runnable {
        ServerSocket serverSocket;

        public PartitionedExecutor(ServerSocket serverSocket) {
            this.serverSocket = serverSocket;
        }

        @Override
        public void run() {
            ExecutorService executors = Executors.newFixedThreadPool(30);
            executors.execute(new NetworkRequestExecutor(serverSocket, executors));
        }
    }


    public static class NetworkRequestExecutor implements Runnable{

        String IGNORE_CHROME = "/favicon.ico";
        String BREAK = "\r\n";
        String DOUBLEBREAK = "\r\n\r\n";

        Integer REQUEST_METHOD = 0;
        Integer REQUEST_PATH = 1;
        Integer REQUEST_VERSION = 2;

        String RENDERER;

        Socket socketClient;
        ExecutorService executors;
        ServerSocket serverSocket;

        public NetworkRequestExecutor(ServerSocket serverSocket, ExecutorService executors){
            this.serverSocket = serverSocket;
            this.executors = executors;
        }

        @Override
        public void run() {
            try {

                socketClient = serverSocket.accept();
                Thread.sleep(19);//do this for safari, its a hack but safari requires something like this.
                InputStream requestInputStream = socketClient.getInputStream();

                OutputStream clientOutput = socketClient.getOutputStream();

                if (requestInputStream.available() == 0) {
                    requestInputStream.close();
                    clientOutput.flush();
                    clientOutput.close();
                    executors.execute(new NetworkRequestExecutor(serverSocket, executors));
                    return;
                }

                ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
                ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
                int bytesRead;
                while ((bytesRead = requestInputStream.read(byteBuffer.array())) != -1) {
                    byteArrayOutputStream.write(byteBuffer.array(), 0, bytesRead);
                    if (requestInputStream.available() == 0) break;
                }

                String completeRequestContent = byteArrayOutputStream.toString();
                String[] requestBlocks = completeRequestContent.split(DOUBLEBREAK, 2);

                String headerComponent = requestBlocks[0];
                String[] methodPathComponentsLookup = headerComponent.split(BREAK);
                String methodPathComponent = methodPathComponentsLookup[0];

                String[] methodPathVersionComponents = methodPathComponent.split("\\s");

                String requestVerb = methodPathVersionComponents[REQUEST_METHOD];
                String requestPath = methodPathVersionComponents[REQUEST_PATH];
                String requestVersion = methodPathVersionComponents[REQUEST_VERSION];


                if (requestPath.equals(IGNORE_CHROME)) {
                    requestInputStream.close();
                    clientOutput.flush();
                    clientOutput.close();
                    executors.execute(new NetworkRequestExecutor(serverSocket, executors));
                    return;
                }

                ConcurrentMap<String, String> headers = new ConcurrentHashMap<>();
                String[] headerComponents = headerComponent.split(BREAK);
                for (String headerLine : headerComponents) {
                    String[] headerLineComponents = headerLine.split(":");
                    if (headerLineComponents.length == 2) {
                        String fieldKey = headerLineComponents[0].trim();
                        String content = headerLineComponents[1].trim();
                        headers.put(fieldKey.toLowerCase(), content);
                    }
                }

                clientOutput.write("HTTP/1.1 200 OK".getBytes());
                clientOutput.write(BREAK.getBytes());

                Integer bytesLength = "hi".length();
                String contentLengthBytes = "Content-Length:" + bytesLength;
                clientOutput.write(contentLengthBytes.getBytes());
                clientOutput.write(BREAK.getBytes());

                clientOutput.write("Server: foo server".getBytes());
                clientOutput.write(BREAK.getBytes());

                clientOutput.write("Content-Type: text/html".getBytes());

                clientOutput.write(DOUBLEBREAK.getBytes());
                clientOutput.write("hi".getBytes());

                clientOutput.close();
                socketClient.close();

                executors.execute(new NetworkRequestExecutor(serverSocket, executors));

            } catch (IOException ex) {
                ex.printStackTrace();
            } catch (InterruptedException ioException) {
                ioException.printStackTrace();
            }
        }
    }
}

运行该程序:

gradle run

浏览:

http://localhost:7654/

以上所有的回答关于单主线程请求处理器的细节。

设置:

 server.setExecutor(java.util.concurrent.Executors.newCachedThreadPool());

允许多个请求服务通过多个线程使用执行器服务。

因此，结束代码将如下所示:

import java.io.IOException;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import com.sun.net.httpserver.HttpServer;
public class App {
    public static void main(String[] args) throws Exception {
        HttpServer server = HttpServer.create(new InetSocketAddress(8000), 0);
        server.createContext("/test", new MyHandler());
        //Thread control is given to executor service.
        server.setExecutor(java.util.concurrent.Executors.newCachedThreadPool());
        server.start();
    }
    static class MyHandler implements HttpHandler {
        @Override
        public void handle(HttpExchange t) throws IOException {
            String response = "This is the response";
            long threadId = Thread.currentThread().getId();
            System.out.println("I am thread " + threadId );
            response = response + "Thread Id = "+threadId;
            t.sendResponseHeaders(200, response.length());
            OutputStream os = t.getResponseBody();
            os.write(response.getBytes());
            os.close();
        }
    }
}

我强烈建议考虑Simple，特别是如果您不需要Servlet功能，而只是访问请求/响应对象。如果你需要REST，你可以把Jersey放在上面，如果你需要输出HTML或类似的东西，有Freemarker。我真的很喜欢使用这个组合可以做的事情，而且需要学习的API相对较少。

从Java SE 6开始，在Sun Oracle JRE中有一个内置的HTTP服务器。Java 9模块名称为jdk.httpserver。httpserver包摘要概述了涉及的类并包含示例。

这里有一个从他们的文档复制粘贴的启动示例。你可以复制，粘贴，然后在Java 6+上运行。 (尽管如此，所有试图编辑它的人，因为它是一段丑陋的代码，请不要，这是一个复制粘贴，不是我的，此外，你不应该编辑引文，除非它们在原始来源中发生了变化)

package com.stackoverflow.q3732109; import java.io.IOException; import java.io.OutputStream; import java.net.InetSocketAddress; import com.sun.net.httpserver.HttpExchange; import com.sun.net.httpserver.HttpHandler; import com.sun.net.httpserver.HttpServer; public class Test { public static void main(String[] args) throws Exception { HttpServer server = HttpServer.create(new InetSocketAddress(8000), 0); server.createContext("/test", new MyHandler()); server.setExecutor(null); // creates a default executor server.start(); } static class MyHandler implements HttpHandler { @Override public void handle(HttpExchange t) throws IOException { String response = "This is the response"; t.sendResponseHeaders(200, response.length()); OutputStream os = t.getResponseBody(); os.write(response.getBytes()); os.close(); } } }

应该注意的是，他们示例中的response.length()部分是坏的，它应该是response.getBytes().length。即使这样，getBytes()方法也必须显式地指定在响应头中指定的字符集。唉，尽管对初学者有误导，但毕竟这只是一个基本的启动示例。

执行它并访问http://localhost:8000/test，你将看到以下响应:

这是反应

As to using com.sun.* classes, do note that this is, in contrary to what some developers think, absolutely not forbidden by the well known FAQ Why Developers Should Not Write Programs That Call 'sun' Packages. That FAQ concerns the sun.* package (such as sun.misc.BASE64Encoder) for internal usage by the Oracle JRE (which would thus kill your application when you run it on a different JRE), not the com.sun.* package. Sun/Oracle also just develop software on top of the Java SE API themselves like as every other company such as Apache and so on. Moreover, this specific HttpServer must be present in every JDK so there is absolutely no means of "portability" issue like as would happen with sun.* package. Using com.sun.* classes is only discouraged (but not forbidden) when it concerns an implementation of a certain Java API, such as GlassFish (Java EE impl), Mojarra (JSF impl), Jersey (JAX-RS impl), etc.

这个代码比我们的代码更好，你只需要添加2个库:javax. servlet .jar和org.mortbay.jetty.jar。

类码头:

package jetty;

import java.util.logging.Level;
import java.util.logging.Logger;
import org.mortbay.http.SocketListener;
import org.mortbay.jetty.Server;
import org.mortbay.jetty.servlet.ServletHttpContext;

public class Jetty {

    public static void main(String[] args) {
        try {
            Server server = new Server();
            SocketListener listener = new SocketListener();      

            System.out.println("Max Thread :" + listener.getMaxThreads() + " Min Thread :" + listener.getMinThreads());

            listener.setHost("localhost");
            listener.setPort(8070);
            listener.setMinThreads(5);
            listener.setMaxThreads(250);
            server.addListener(listener);            

            ServletHttpContext context = (ServletHttpContext) server.getContext("/");
            context.addServlet("/MO", "jetty.HelloWorldServlet");

            server.start();
            server.join();

        /*//We will create our server running at http://localhost:8070
        Server server = new Server();
        server.addListener(":8070");

        //We will deploy our servlet to the server at the path '/'
        //it will be available at http://localhost:8070
        ServletHttpContext context = (ServletHttpContext) server.getContext("/");
        context.addServlet("/MO", "jetty.HelloWorldServlet");

        server.start();
        */

        } catch (Exception ex) {
            Logger.getLogger(Jetty.class.getName()).log(Level.SEVERE, null, ex);
        }

    }
} 

Servlet类:

package jetty;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class HelloWorldServlet extends HttpServlet
{
    @Override
    protected void doGet(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse) throws ServletException, IOException
    {
        String appid = httpServletRequest.getParameter("appid");
        String conta = httpServletRequest.getParameter("conta");

        System.out.println("Appid : "+appid);
        System.out.println("Conta : "+conta);

        httpServletResponse.setContentType("text/plain");
        PrintWriter out = httpServletResponse.getWriter();
        out.println("Hello World!");
        out.close();
    }
}