Maven编译和运行时错误java.lang.AbstractMethodError：Tomcat 8 Server上的oracle.jdbc.driver.T4CConnection.isValid（I）Z

Question

I've been converting a large Java Web App to a maven project, but I've run into an error in a handful of classes originating from the tomcat-dbcp jar. I get the following error messages from any class that needs to use BasicDataSource objects:

javax.servlet.ServletException: java.lang.AbstractMethodError: oracle.jdbc.driver.T4CConnection.isValid(I)Z
java.lang.AbstractMethodError: oracle.jdbc.driver.T4CConnection.isValid(I)Z

Now I know this jar is present on the server (as it is default in our Tomcat8 installation). So in maven I declared this dependency as such:

<dependency>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat-dbcp</artifactId>
    <version>8.0.26</version>
    <scope>provided</scope>
</dependency>

But I'm still seeing this error. What can I do to eliminate this error?

Answer 1

This error did go away, though I have no idea why. The pom entry is still the same and still running on Tomcat 8. We did find a hacky temporary fix:

<dependency>
    <groupId>com.oracle</groupId>
    <artifactId>ojdbc7</artifactId>
    <version>12.1.0.1</version>
    <scope>system</scope>
    <systemPath>${basedir}/lib/ojdbc7-12.1.0.1.jar</systemPath>
</dependency>

But we reverted back at some point and it is working fine.