多线程 Java HTTP 服务器

Question

我在我的应用程序中使用 sun.net.httpServer 到运行 HTTP 服务器（不要问我为什么）。

问题是它只在一个线程中处理我的请求，所以我的吞吐量是一场灾难。

我想如果我 setExecutor 我的 httpServer 这个问题会得到解决，但我开始在我的服务器端和客户端出现异常 (SOAP-UI ).我测试了各种执行器，包括 Executors.newCachedThreadPool 、 Executors.newFixedThreadPool、Executors.newWorkStealingPool、Executors.newScheduledThreadPool 没有任何运气。

正如我所说，当我从 setExecutor 到 null 时，我的代码工作正常，但在此配置中，我的代码按顺序处理请求。

我不知道该怎么办。这是我的代码：

public class HTTPListener {
    private HttpServer httpServer;
    private int port = 1253;

    public void stop() {
        if (httpServer != null) {
            httpServer.stop(0);
            httpServer = null;
        }
    }
    public void startHTTPServer() {
        try {
            httpServer = HttpServer.create(new InetSocketAddress(1252), 100);
            httpServer.setExecutor(null);
            httpServer.createContext("/", new RequestHandler());
            httpServer.start();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

当我设置执行器时出现此错误

java.io.IOException: stream closed
    at sun.net.httpserver.FixedLengthOutputStream.write(FixedLengthOutputStream.java:68)
    at sun.net.httpserver.PlaceholderOutputStream.write(ExchangeImpl.java:444)
    at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:82)
    at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:140)
    at java.io.FilterOutputStream.close(FilterOutputStream.java:158)
    at com.RequestHandler.sendResponse(RequestHandler.java:61)
    at com..RequestHandler.handle(RequestHandler.java:18)
    at com.sun.net.httpserver.Filter$Chain.doFilter(Filter.java:79)
    at sun.net.httpserver.AuthFilter.doFilter(AuthFilter.java:83)
    at com.sun.net.httpserver.Filter$Chain.doFilter(Filter.java:82)
    at sun.net.httpserver.ServerImpl$Exchange$LinkHandler.handle(ServerImpl.java:675)
    at com.sun.net.httpserver.Filter$Chain.doFilter(Filter.java:79)
    at sun.net.httpserver.ServerImpl$Exchange.run(ServerImpl.java:645)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

这是我的 RequestHandler Class:

public class RequestHandler implements HttpHandler {
    private HttpExchange sender;

    @Override
    public void handle(HttpExchange httpExchange) throws IOException {
        this.sender = httpExchange;
        try {
            String request = readRequestBody();
            sendResponse(200, "Hello World !");
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            this.sender.close();
        }
    }

    private String readRequestBody() throws Exception {
        try (InputStream isr = sender.getRequestBody()) {
            byte[] buffer = new byte[isr.available()];
            isr.read(buffer);
            return Arrays.toString(buffer);
        } catch (IOException ex) {
            throw new Exception(ex.getMessage());
        }
    }

    private void sendResponse(int httpResponseCode, String response) throws IOException {
        OutputStream outputStream = null;
        try {
            sender.getResponseHeaders().set("Content-Type", "text/html; charset=UTF-8");
            sender.sendResponseHeaders(httpResponseCode, response.length());
            outputStream = sender.getResponseBody();
            outputStream.write(response.getBytes());
        } finally {
            if (outputStream != null)
                outputStream.close();
        }

    }
}

而且我在客户端也收到了这个错误代码

org.apache.http.ConnectionClosedException: Premature end of Content-Length delimited message body (expected: 13; received: 0
    at org.apache.http.impl.io.ContentLengthInputStream.read(ContentLengthInputStream.java:180)
    at org.apache.http.conn.EofSensorInputStream.read(EofSensorInputStream.java:137)
    at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:284)
    at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:326)
    at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:178)
    at java.io.InputStreamReader.read(InputStreamReader.java:184)
    at java.io.Reader.read(Reader.java:140)
    at org.apache.http.util.EntityUtils.toString(EntityUtils.java:247)
    at org.apache.http.util.EntityUtils.toString(EntityUtils.java:291)
    at Business.HTTPHandler.Client.send(Client.java:68)
    at main.Main.lambda$main(Main.java:86)
    at java.lang.Thread.run(Thread.java:745)

    org.apache.http.client.ClientProtocolException
    at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:186)
    at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82)
    at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:107)
    at Business.HTTPHandler.Client.send(Client.java:67)
    at main.Main.lambda$main(Main.java:86)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.http.ProtocolException: Invalid header: *
    at org.apache.http.impl.io.AbstractMessageParser.parseHeaders(AbstractMessageParser.java:232)
    at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:268)
    at org.apache.http.impl.DefaultBHttpClientConnection.receiveResponseHeader(DefaultBHttpClientConnection.java:165)
    at org.apache.http.impl.conn.CPoolProxy.receiveResponseHeader(CPoolProxy.java:167)
    at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:272)
    at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:124)
    at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:271)
    at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:184)
    at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:88)
    at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:110)
    at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:184)
    ... 5 more

    Caused by: org.apache.http.ProtocolException: Invalid header: 13
    at org.apache.http.impl.io.AbstractMessageParser.parseHeaders(AbstractMessageParser.java:232)
    at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:268)
    at org.apache.http.impl.DefaultBHttpClientConnection.receiveResponseHeader(DefaultBHttpClientConnection.java:165)
    at org.apache.http.impl.conn.CPoolProxy.receiveResponseHeader(CPoolProxy.java:167)
    at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:272)
    at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:124)
    at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:271)
    at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:184)
    at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:88)
    at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:110)
    at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:184)
    ... 5 more

Answer 1

你的 RequestHandler class 不是线程安全的，这就是为什么它在你运行单线程时有效而在使用执行程序时失败的原因。

不要将HttpExchange对象存储在sender变量中。当所有线程都覆盖同一个变量时，它会导致竞争条件，并且可能看到处于错误状态的错误对象（例如，已经关闭流的对象）。

您可以将其作为参数传递给您的方法。你真的不需要额外的变量。

多线程 Java HTTP 服务器

Multi-Threaded Java HTTP-Server

java

com.sun.net.httpserver