调试，测试并调整修改了代码及结构

.settings/org.eclipse.wst.common.project.facet.core.xml

@@ -1,10 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<faceted-project>
-  <runtime name="Apache Tomcat v9.0"/>
-  <fixed facet="java"/>
-  <fixed facet="wst.jsdt.web"/>
-  <fixed facet="jst.web"/>
-  <installed facet="java" version="1.8"/>
-  <installed facet="jst.web" version="4.0"/>
-  <installed facet="wst.jsdt.web" version="1.0"/>
-</faceted-project>