The valid characters are defined in RFC 7230 and RFC 3986

 错误日志

HTTP Status 400 – Bad Request
Type Exception Report

Message Invalid character found in the request target [/baidu/baidu.gif?event=mousedown&sr=1280*720&br=1263*609&dpr=1.5000&clicktype=3&url=http%3A%2F%2F120.221.95.164%3A9000%2F&br=1263*609&pa=[{x:355,y:66}]&pb=[{z:-285,y:66}]]. The valid characters are defined in RFC 7230 and RFC 3986

Description The server cannot or will not process the request due to something that is perceived to be a client error (e.g., malformed request syntax, invalid request message framing, or deceptive request routing).

Exception

java.lang.IllegalArgumentException: Invalid character found in the request target [/baidu/baidu.gif?event=mousedown&sr=1280*720&br=1263*609&dpr=1.5000&clicktype=3&url=http%3A%2F%2F120.221.95.164%3A9000%2F&br=1263*609&pa=[{x:355,y:66}]&pb=[{z:-285,y:66}]]. The valid characters are defined in RFC 7230 and RFC 3986
	org.apache.coyote.http11.Http11InputBuffer.parseRequestLine(Http11InputBuffer.java:486)
	org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:261)
	org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
	org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
	org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590)
	org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	java.lang.Thread.run(Thread.java:745)
Note The full stack trace of the root cause is available in the server logs.

解决方案：

本环境中的Tomcat版本为9.0.38

#修改server.xml配置文件

<Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" relaxedQueryChars="[]|{}^&#x5c;&#x60;&quot;&lt;&gt;" redirectPort="8443" />

修改后重新启动Tomcat ,完美解决