Hi Zhiping, I am pulling in Timo who knows the sql client probably best. He might be able to help you. In general, this sounds like a bug to me. Maybe you can provide us with the full stack trace and maybe even the debug logs of the failing run.
Cheers, Till On Sun, Jan 30, 2022 at 4:21 AM Zhiping Wu <stayras...@gmail.com> wrote: > Hi there, > > I'm trying to consult whether a flink class loader(ParentFirstClassLoader > or ChildFirstClassLoader) must be a singleton? > > I met a problem with the below error message by using sql-client to submit > sql jobs to a standalone session model cluster with Flink 1.13.3. > I also tried ParentFirstClassLoader & ChildFirstClassLoader, both of them > will meet this problem. > > Caused by: java.lang.ClassCastException: > class org.apache.hudi.common.fs.HoodieWrapperFileSystem cannot be cast to > class org.apache.hudi.common.fs.HoodieWrapperFileSystem > (org.apache.hudi.common.fs.HoodieWrapperFileSystem > is in unnamed module of loader > org.apache.flink.runtime.execution.librarycache. > FlinkUserCodeClassLoaders$ParentFirstClassLoader @*384d2142*; > org.apache.hudi.common.fs.HoodieWrapperFileSystem > is in unnamed module of loader > org.apache.flink.runtime.execution.librarycache. > FlinkUserCodeClassLoaders$ParentFirstClassLoader @*35e21dd1*) > > From this documentation, it shows I might have two versions of the class > which are different in application code and flink libraries. > But in my case, Flink should don't contains HoodieWrapperFileSystem class, > and I didn't add the hudi-flink-bundle jar to flink lib folder, instead, i > used sql-client.sh embedded -j xxxx/huid-flink-bundle-xxx.jar. > > So I'm wondering if the root reason is that they are loaded by two > classloader instances? And it seems that FlinkUserCodeClassLoaders is a > singleton, but ParentFirstClassLoader and ChildFirstClassLoader aren't from > flink source code. >
