[Java知识库]原因:java.lang.IllegalArgumentException:找到多个名为[spring |u web]的片段。这是不合法的相对秩序。有关详细信息请参阅Servlet规范的第8.2.2c

问题前面说的查看：
https://www.oracle.com/technical-resources/articles/java/javaee6overview-part2.html
关于servlet的规范


Servlet 3.0 supports absolute ordering and relative ordering of deployment descriptors. Your specify absolute ordering using the element in the web.xml file. You specify relative ordering with an element in the web-fragment.xml file.
Servlet 3.0 supports absolute ordering and relative ordering of deployment descriptors. Your specify absolute ordering using the element in the web.xml file. You specify relative ordering with an element in the web-fragment.xml file.

For example, suppose your application includes two web fragments — MyFragment2 and MyFragment3, and also includes a web.xml file. You can declare absolute ordering of the descriptors by specifying the following in the web.xml file for the application:
也就是上面我的截图

也就是在web.xml中添加<absolute_ordering/>可以解决