启动Tomcat9服务器时DataSourceFactory的java NoClassDefFoundError？

Question

我正在将一个JAR文件部署到classpath/lib文件夹中，该文件夹包含org.apache.tomcat.jdbc.pool.DataSourceFactory的自定义子类，并将其作为工厂类提供给server.xml中数据源的Resource标记。正在添加适当的库（因此没有编译时错误），但在启动服务器时，它会给出以下错误日志，并且无法启动：

SEVERE: The required Server component failed to start so Tomcat is unable to start.
org.apache.catalina.LifecycleException: Failed to start component [StandardServer[8013]]
    at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:441)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:198)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:682)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:350)
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:492)
Caused by: java.lang.NoClassDefFoundError: org/apache/tomcat/jdbc/pool/DataSourceFactory
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at java.security.SecureClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.access$100(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at org.apache.naming.factory.FactoryBase.getObjectInstance(FactoryBase.java:61)
    at javax.naming.spi.NamingManager.getObjectInstance(Unknown Source)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:840)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:159)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:827)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:173)
    at org.apache.catalina.core.NamingContextListener.addResource(NamingContextListener.java:1015)
    at org.apache.catalina.core.NamingContextListener.createNamingContext(NamingContextListener.java:556)
    at org.apache.catalina.core.NamingContextListener.lifecycleEvent(NamingContextListener.java:252)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:123)
    at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:762)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    ... 7 more
Caused by: java.lang.ClassNotFoundException: org.apache.tomcat.jdbc.pool.DataSourceFactory
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    ... 32 more

有人能帮我吗？任何信息都会有帮助。提前谢谢；-）