问题背景

关于SpringBoot应用挂了很久之后，会发生Invalid character found in method name. HTTP method names must be tokens的问题。

java.lang.IllegalArgumentException: Invalid character found in method name. HTTP method names must be tokens
	at org.apache.coyote.http11.Http11InputBuffer.parseRequestLine(Http11InputBuffer.java:426) ~[tomcat-embed-core-8.5.29.jar:8.5.29]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:687) ~[tomcat-embed-core-8.5.29.jar:8.5.29]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.29.jar:8.5.29]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) [tomcat-embed-core-8.5.29.jar:8.5.29]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459) [tomcat-embed-core-8.5.29.jar:8.5.29]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.29.jar:8.5.29]
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1135) [na:na]
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) [na:na]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.29.jar:8.5.29]
	at java.base/java.lang.Thread.run(Thread.java:844) [na:na]

网上方案

据说是tomcat 的设置问题，如果出现相关情况，可以设置一下application.yml文件的tomcat下的max-http-header-size即可。

server:
  port: 5555
  servlet:
      context-path: /xxxx
  tomcat:
      remote-ip-header: x-forward-for
      uri-encoding: UTF-8
      max-threads: 1000
      max-http-header-size: 8096

实际情况

发现是正常的http请求，发送为https请求。
例如正常路径为http://localhost:8080/xxxx，现在变成请求https://localhost:8080/xxxx就会报错。(似乎跟项目没有什么关系).

猜测

可能是tomcat8.5的keepalive有关,检测自己http协议的时候顺便检测了自己的https协议,有很多人遇到半夜报错或者隔了一段时间报错,目前这个bug没搜索到很多定论,可以尝试加tomcat的connection-timeout

parseRequestLine

报错的地方代码如下

org.apache.coyote.http11.Http11InputBuffer.parseRequestLine

    /**
     * Read the request line. This function is meant to be used during the
     * HTTP request header parsing. Do NOT attempt to read the request body
     * using it.
     *
     * @throws IOException If an exception occurs during the underlying socket
     * read operations, or if the given buffer is not big enough to accommodate
     * the whole line.
     * @return true if data is properly fed; false if no data is available
     * immediately and thread should be freed
     */
    boolean parseRequestLine(boolean keptAlive) throws IOException {

        // check state
        if (!parsingRequestLine) {
            return true;
        }
        //
        // Skipping blank lines
        //
        if (parsingRequestLinePhase < 2) {
            byte chr = 0;
            do {

                // Read new bytes if needed
                if (byteBuffer.position() >= byteBuffer.limit()) {
                    if (keptAlive) {
                        // Haven't read any request data yet so use the keep-alive
                        // timeout.
                        wrapper.setReadTimeout(wrapper.getEndpoint().getKeepAliveTimeout());
                    }
                    if (!fill(false)) {
                        // A read is pending, so no longer in initial state
                        parsingRequestLinePhase = 1;
                        return false;
                    }
                    // At least one byte of the request has been received.
                    // Switch to the socket timeout.
                    wrapper.setReadTimeout(wrapper.getEndpoint().getConnectionTimeout());
                }
                if (!keptAlive && byteBuffer.position() == 0 && byteBuffer.limit() >= CLIENT_PREFACE_START.length - 1) {
                    boolean prefaceMatch = true;
                    for (int i = 0; i < CLIENT_PREFACE_START.length && prefaceMatch; i++) {
                        if (CLIENT_PREFACE_START[i] != byteBuffer.get(i)) {
                            prefaceMatch = false;
                        }
                    }
                    if (prefaceMatch) {
                        // HTTP/2 preface matched
                        parsingRequestLinePhase = -1;
                        return false;
                    }
                }
                // Set the start time once we start reading data (even if it is
                // just skipping blank lines)
                if (request.getStartTime() < 0) {
                    request.setStartTime(System.currentTimeMillis());
                }
                chr = byteBuffer.get();
            } while ((chr == Constants.CR) || (chr == Constants.LF));
            byteBuffer.position(byteBuffer.position() - 1);

            parsingRequestLineStart = byteBuffer.position();
            parsingRequestLinePhase = 2;
            if (log.isDebugEnabled()) {
                log.debug("Received [" + new String(byteBuffer.array(), byteBuffer.position(), byteBuffer.remaining(),
                        StandardCharsets.ISO_8859_1) + "]");
            }
        }
        if (parsingRequestLinePhase == 2) {
            //
            // Reading the method name
            // Method name is a token
            //
            boolean space = false;
            while (!space) {
                // Read new bytes if needed
                if (byteBuffer.position() >= byteBuffer.limit()) {
                    if (!fill(false)) // request line parsing
                        return false;
                }
                // Spec says method name is a token followed by a single SP but
                // also be tolerant of multiple SP and/or HT.
                int pos = byteBuffer.position();
                byte chr = byteBuffer.get();
                if (chr == Constants.SP || chr == Constants.HT) {
                    space = true;
                    request.method().setBytes(byteBuffer.array(), parsingRequestLineStart,
                            pos - parsingRequestLineStart);
                } else if (!HttpParser.isToken(chr)) {
                    byteBuffer.position(byteBuffer.position() - 1);
                    throw new IllegalArgumentException(sm.getString("iib.invalidmethod"));
                }
            }
            parsingRequestLinePhase = 3;
        }
        if (parsingRequestLinePhase == 3) {
            // Spec says single SP but also be tolerant of multiple SP and/or HT
            boolean space = true;
            while (space) {
                // Read new bytes if needed
                if (byteBuffer.position() >= byteBuffer.limit()) {
                    if (!fill(false)) // request line parsing
                        return false;
                }
                byte chr = byteBuffer.get();
                if (!(chr == Constants.SP || chr == Constants.HT)) {
                    space = false;
                    byteBuffer.position(byteBuffer.position() - 1);
                }
            }
            parsingRequestLineStart = byteBuffer.position();
            parsingRequestLinePhase = 4;
        }
        if (parsingRequestLinePhase == 4) {
            // Mark the current buffer position

            int end = 0;
            //
            // Reading the URI
            //
            boolean space = false;
            while (!space) {
                // Read new bytes if needed
                if (byteBuffer.position() >= byteBuffer.limit()) {
                    if (!fill(false)) // request line parsing
                        return false;
                }
                int pos = byteBuffer.position();
                byte chr = byteBuffer.get();
                if (chr == Constants.SP || chr == Constants.HT) {
                    space = true;
                    end = pos;
                } else if (chr == Constants.CR || chr == Constants.LF) {
                    // HTTP/0.9 style request
                    parsingRequestLineEol = true;
                    space = true;
                    end = pos;
                } else if (chr == Constants.QUESTION && parsingRequestLineQPos == -1) {
                    parsingRequestLineQPos = pos;
                } else if (HttpParser.isNotRequestTarget(chr)) {
                    throw new IllegalArgumentException(sm.getString("iib.invalidRequestTarget"));
                }
            }
            if (parsingRequestLineQPos >= 0) {
                request.queryString().setBytes(byteBuffer.array(), parsingRequestLineQPos + 1,
                        end - parsingRequestLineQPos - 1);
                request.requestURI().setBytes(byteBuffer.array(), parsingRequestLineStart,
                        parsingRequestLineQPos - parsingRequestLineStart);
            } else {
                request.requestURI().setBytes(byteBuffer.array(), parsingRequestLineStart,
                        end - parsingRequestLineStart);
            }
            parsingRequestLinePhase = 5;
        }
        if (parsingRequestLinePhase == 5) {
            // Spec says single SP but also be tolerant of multiple and/or HT
            boolean space = true;
            while (space) {
                // Read new bytes if needed
                if (byteBuffer.position() >= byteBuffer.limit()) {
                    if (!fill(false)) // request line parsing
                        return false;
                }
                byte chr = byteBuffer.get();
                if (!(chr == Constants.SP || chr == Constants.HT)) {
                    space = false;
                    byteBuffer.position(byteBuffer.position() - 1);
                }
            }
            parsingRequestLineStart = byteBuffer.position();
            parsingRequestLinePhase = 6;

            // Mark the current buffer position
            end = 0;
        }
        if (parsingRequestLinePhase == 6) {
            //
            // Reading the protocol
            // Protocol is always "HTTP/" DIGIT "." DIGIT
            //
            while (!parsingRequestLineEol) {
                // Read new bytes if needed
                if (byteBuffer.position() >= byteBuffer.limit()) {
                    if (!fill(false)) // request line parsing
                        return false;
                }

                int pos = byteBuffer.position();
                byte chr = byteBuffer.get();
                if (chr == Constants.CR) {
                    end = pos;
                } else if (chr == Constants.LF) {
                    if (end == 0) {
                        end = pos;
                    }
                    parsingRequestLineEol = true;
                } else if (!HttpParser.isHttpProtocol(chr)) {
                    throw new IllegalArgumentException(sm.getString("iib.invalidHttpProtocol"));
                }
            }

            if ((end - parsingRequestLineStart) > 0) {
                request.protocol().setBytes(byteBuffer.array(), parsingRequestLineStart, end - parsingRequestLineStart);
            } else {
                request.protocol().setString("");
            }
            parsingRequestLine = false;
            parsingRequestLinePhase = 0;
            parsingRequestLineEol = false;
            parsingRequestLineStart = 0;
            return true;
        }
        throw new IllegalStateException("Invalid request line parse phase:" + parsingRequestLinePhase);
    }