笔者最近使用tomcat9,由于工作洁癖，盯上了tomcat启动日志里的"No TLD files were found in"字样，如下
15-Sep-2017 02:19:09.685 FINE [main] org.apache.jasper.servlet.TldScanner$TldScannerCallback.scan No TLD files were found in [file:/home/tomcat9/webapps/xxx/WEB-INF/lib/z-1.1.3.jar]. Consider adding the JAR to the tomcat.util.scan.StandardJarScanFilter.jarsToSkip property in CATALINA_BASE/conf/catalina.properties file.
于是按照以下stackoverflow两篇文章进行优化
How to fix “JARs that were scanned but no TLDs were found in them ” in Tomcat 9.0.0M10
How to fix JSP compiler warning: one JAR was scanned for TLDs yet contained no TLDs?
把z-1.1.3.jar添加到了${catalina.base}/conf/catalina.properties里面，如下
tomcat.util.scan.StandardJarScanFilter.jarsToSkip=z-1.1.3.jar
结果吧z-1.1.3.jar每次上传到WEB_INF/lib/目录下tomcat都能正常运行，可是与预期的结果不一致，最终经过排查发现了这个原因。
解决方法：把z-1.1.3.jar从jarSkip去掉重启tomcat即可。
其他资源:
Logging in Tomcat tomcat全局日志记录与web应用日志记录