GitHub user rmannibucau opened a pull request: https://github.com/apache/beam/pull/3871
[BEAM-2701] ensure objectinputstream uses the right classloader for serialization When the PTransform are not loaded with the app classloader the ensureSerializable code can end up through ObjectInputStream on vmLatestUserDefinedClassLoader which likely falls back on app classloader whereas it should use the TCCL in resolveClass. This PR ensures: 1. we use the TCCL as expected to deserialize an instance 2. uses the serialized instance classloader contextually in ensureSerializable to tolerate cross classloader usage You can merge this pull request into a Git repository by running: $ git pull https://github.com/rmannibucau/incubator-beam fix/serialization-classloader Alternatively you can review and apply these changes as the patch at: https://github.com/apache/beam/pull/3871.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #3871 ---- commit 0c3d743f50a8c40fb1f064886996941af37fb8c8 Author: Romain Manni-Bucau <rmannibu...@gmail.com> Date: 2017-09-20T15:29:53Z ensure objectinputstream uses the right classloader for serialization ---- ---