java.lang.IllegalArgumentException: Invalid character found in method name. HTTP method names must be tokens

服务器没人访问，开着日志，发现个报错，但也不影响系统正常运行

2016-11-16 15:49:54,447 [http-bio-80-exec-41][IP:|USER:][DEBUG org.springframework.web.servlet.DispatcherServlet] Successfully completed request
Nov 16, 2016 4:12:54 PM org.apache.coyote.http11.AbstractHttp11Processor process
INFO: 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.InternalInputBuffer.parseRequestLine(InternalInputBuffer.java:135)
  at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:996)
  at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:623)
  at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
  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)

经过查阅资料发现是Tomcat的header缓冲区大小不够,只需要在server.xml中增加maxHttpHeaderSize字段即可:

<Connector URIEncoding="UTF-8" port="8080" protocol="org.apache.coyote.http11.Http11NioProtocol"
	useBodyEncodingForURI="false"
	enableLookups="false"
        connectionTimeout="20000"
        redirectPort="8443" maxHttpHeaderSize="8192"/>