tomcat7.0.70 启动报错java.lang.NoSuchMethodException: org.apache.catalina.deploy.WebXml addServlet

tomcat7.0.70 启动报错信息如下：

十一月 10, 2017 9:02:05 上午 org.apache.catalina.loader.WebappClassLoaderBase validateJarFile

信息: validateJarFile(C:\apache-tomcat-7.0.70\webapps\test\WEB-INF\lib\tomcat-servlet-api-7.0.70.jar) - jar not loaded. See Servlet Spec 3.0, section 10.7.2. Offending class: javax/servlet/Servlet.class
十一月 10, 2017 9:02:05 上午 org.apache.tomcat.util.digester.Digester endElement
严重: End event threw exception
java.lang.NoSuchMethodException: org.apache.catalina.deploy.WebXml addServlet
at org.apache.tomcat.util.IntrospectionUtils.callMethod1(IntrospectionUtils.java:849)
at org.apache.tomcat.util.digester.SetNextRule.end(SetNextRule.java:201)
at org.apache.tomcat.util.digester.Digester.endElement(Digester.java:1060)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.endElement(AbstractSAXParser.java:609)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanEndElement(XMLDocumentFragmentScannerImpl.java:1782)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2973)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:606)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:510)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:848)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:777)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1213)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:648)
at org.apache.tomcat.util.digester.Digester.parse(Digester.java:1555)
at org.apache.catalina.startup.ContextConfig.parseWebXml(ContextConfig.java:1856)
at org.apache.catalina.startup.ContextConfig.getDefaultWebXmlFragment(ContextConfig.java:1494)
at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1255)
at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:887)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:387)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5503)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:147)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1571)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1561)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)

at java.lang.Thread.run(Thread.java:745)

检查发现我test项目使用maven引入了tomcat7的jar包，

        <dependency>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat-catalina</artifactId>
    <version>7.0.70</version>
</dependency>

类加载器没有加载该jar  

原因应该是类加载器直接加载tomcatlib下的jar，

解决方法1，%TOMCAT_HOME%/conf/context.xml 中添加 <Loader delegate="true">

          设置tomcat将遵循JVM的delegate机制,能够解决该冲突

解决方法2，将maven引入的tomcatjar包去除