找到 \项目名\.setting\文件夹下的 org.eclipse.wst.common.project.facet.core.xml xml文件。
添加或修改
<installed facet="jst.web" version="2.5"/>
修改后
<?xml version="1.0" encoding="UTF-8"?>
<faceted-project>
<installed facet="java" version="1.7"/>
<installed facet="jst.web" version="2.5"/>
<installed facet="me.spring" version="4.1"/>
<installed facet="jst.utility" version="1.0"/>
<installed facet="maven" version="1.0"/>
</faceted-project>>