這幾天專案總是在凌晨掛機，檢視日誌發現以下錯誤：

Http11Processor - Error parsing HTTP request header
 Note: further occurrences of HTTP header parsing errors will be logged at DEBUG level.
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)
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:687)
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459)
        at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
        at java.lang.Thread.run(Thread.java:745)

Http11Processor - Error parsing HTTP request header
 Note: further occurrences of HTTP header parsing errors will be logged at DEBUG level.
java.lang.IllegalArgumentException: Invalid character found in the HTTP protocol
        at org.apache.coyote.http11.Http11InputBuffer.parseRequestLine(Http11InputBuffer.java:533)
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:687)
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459)
        at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
        at java.lang.Thread.run(Thread.java:745)
 

那麼可能需要通過以下兩種方式解決：

一、Tomcat的header緩衝區大小不夠,只需要在server.xml中增加maxHttpHeaderSize欄位即可:

    <Connector URIEncoding="UTF-8" port="8080" protocol="org.apache.coyote.http11.Http11NioProtocol"
useBodyEncodingForURI="false"
enableLookups="false"
               connectionTimeout="20000"

               redirectPort="8443" maxHttpHeaderSize="你想要的大小"/>

    如果是SpringBoot專案，則需要在application.yml檔案中，進行如下修改：

server:
  port: 專案埠
  # 下面這個引數是為解決問題而新增的
  tomcat:
    max-http-header-size: 8192