Tomcat 7 解决“At least one JAR was scanned for TLDs yet contained no TLDs” 的一种思路

tomcat版本 apache-tomcat-7.0.85
错误表现：出现“At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time”
解决方案：
1.将log4j.properties增加工程，前题是之前导入了相应的jar包。
2.打印出日志，定位错误日志
发现错误日志中有：”…Result Maps collection already contains value forxxx…”
3.到对应的xml文件，发现有相同的id。
4.找到原因：自动生成xml的时候原来的xml没有删除。
再次生成代码时，又附加了上去！所以在运行代码生成之前，要把以前已经生成的xml文件清掉，以防出错。
清除所有自动生成的class,interface,xml.然后重新生成，问题解决。
5.删除log4j.properties。