The valid characters are defined in RFC 7230 and RFC 3986

完整报错：

org.apache.coyote.http11.Http11Processor.service 解析 HTTP 请求 header 错误
 Note: further occurrences of HTTP request parsing errors will be logged at DEBUG level.
        java.lang.IllegalArgumentException: Invalid character found in the request target. The valid characters are defined in RFC 7230 and RFC 3986
                at org.apache.coyote.http11.Http11InputBuffer.parseRequestLine(Http11InputBuffer.java:483)
                at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:502)
                at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
                at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:818)
                at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1623)
                at org.apache.tomcat.util.net.socketProcessorBase.run(SocketProcessorBase.java:49)
                at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
                at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
                at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
                at java.lang.Thread.run(Thread.java:748)

错误原因：

1. 请求内容中包含特殊字符
2. 浏览器get请求传入参数长度过长
3. tomcat版本过高

解决办法：

1. 页面级解决办法：使用js自带的函数encodeURIComponent(inInfo)将包含特殊字符的字符串转义
2. tomcat级解决办法：

        （1.） 修改tomcat/config下的catalina.properties文件：

tomcat.util.http.parser.HttpParser.requestTargetAllow=|{}

                        或者

org.apache.tomcat.util.buf.UDecoder.ALLOW_ENCODED_SLASH=true

       （2.） 修改tomcat/config下的server.xml文件中

 <Connector port="9080" protocol="HTTP/1.1"
               connectionTimeout="20000"   URIEncoding="UTF-8" 
               maxHttpHeaderSize ="22240"
               relaxedpathChars="[]{}|^"
               relaxedQueryChars="{,}"
               redirectPort="8443" />