I am sorry to say that I do not have a well-oiled solution for you. The
apps I've written that use DBCP2 do so directly. The Spring Batch I wrote I
have uses plain JDBC. Hopefully someone else here has a workaround for you.
Gary
On Wed, Aug 19, 2020 at 7:20 PM BRUNO MELLONI <bruno.mell...@chickasaw.net>
wrote:
> I happily used DBCP and DBCP2 with Spring for over a decade. I am now
> trying to migrate from Java 8 to Java 11 and hit a terrible snag, described
> below:
>
>
> * My apps dynamically load the classpath from a tree of folder that
> contains many JARs. Yes, I can change this model in the future but for now
> I need to migrate many apps quickly and that means keeping this design.
>
> * The old techniques to do the above broke starting in Java 9, so I
> must now use a custom classloader. That was easy to write, and I set it
> with thread.setContextClassLoader(myClassloader). From that point on in
> "vanilla" Java my apps find the classes fine as all the needed libraries
> are in the classpath.
>
> * But I define my DBCP2 DataSource in a Spring context.xml file.
> This is where things break.
>
> o I get a ClassNotFoundException for org.apache.commons.pool2.ObjectPool
> when loaded indirectly by the Spring bean specified with
> class="org.apache.commons.dbcp2.BasicDataSource".
>
> o Curiously, I can successfully load the class manually with
> myClassloader.loadClass("org.apache.commons.pool2.ObjectPool") in my code
> just fine, confirming that it is properly on the classloader's classpath.
>
> * My conclusion (maybe erroneous) is that Spring is reverting to the
> system classloader instead of using myClassloader when loading classes,
> because at the time of execution (and exception) the commons-pool2 JAR is
> only known to myClassloader, not the system classloader.
>
> I suspect that the core of this problem is more about Java 11 or even
> Spring than DBCP2. But as most applications that rely on DBCP2 do it
> through Spring, a lot of us are migrating out of Java 8, and this issue
> cripples those DBCP2-reliant applications... I am hoping that there is a
> well-known solution and someone here will be kind enough to share it.
>
> Thank you in advance.
>
