SSM整合，在进行单元测试时，会报下面的警告。
log4j:WARN No appenders could be found for logger (org.springframework.test.context.junit4.SpringJUnit4ClassRunner).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
HttpPutFormContentFilter过滤器会自动的封装前台传递过来的PUT请求的参数，如果不配置HttpPutFormContentFilter过滤器的话，那么tomcat便不会自主的分封装PUT请求的参数。
<filter> <filter-name> HttpPutFormContentFilter </filter-name> <filter-class> org.springframework.web.filter.HttpPutFormContentFilter </filter-class> </filter> <filter-mapping> <filter-name> HttpPutFormContentFilter </filter-name> <url-pattern> /* </url-pattern> </filter-mapping>
但现在官方已经不再推荐使用该配置。