Context} Setting property 'source' to 'org.eclipse.jst.jee.server:reyo' did not find a matching property.

解决办法是：关闭tomcat，双击eclipse下tomcat服务器，在出来的Tomcat server at localhost页面中找到server options选项，选中其中的选项”Publish modual contexts to separat XML files“，ctr+s，启动tomcat。