[move-hoon]

What is this PR for?

PySpark and PyFlink currently define their ZeppelinContext subclasses separately in the classic Python and IPython bootstrap resources, even though the implementations are effectively the same for each backend.

This PR moves the PySpark and PyFlink implementations into the shared zeppelin_context.py resource and reuses them from both bootstrap paths.

Backend-specific behavior remains unchanged:

• PySpark handles Spark DataFrame objects through _jdf.
• PyFlink handles Flink Table objects through _j_table.
• PyFlink retains support for the stream_type argument.
• Other object types fall back to PyZeppelinContext.show().
• IPySparkZeppelinContext and IPyFlinkZeppelinContext remain available as compatibility aliases.

No new dependencies are introduced.

What type of PR is it?

Refactoring

Todos

• Move the PySpark ZeppelinContext implementation to the shared resource
• Move the PyFlink ZeppelinContext implementation to the shared resource
• Reuse the shared implementations from Python and IPython bootstraps
• Keep the existing IPython class names as compatibility aliases
• Verify Spark and Flink interpreter packaging
• Verify PySpark z.show(DataFrame) behavior

What is the Jira issue?

https://issues.apache.org/jira/browse/ZEPPELIN-6457

How should this be tested?

The following checks passed successfully:

./mvnw test \
  -pl python \
  -Dtest=PythonInterpreterTest#testBackendZeppelinContextsAvailable \
  -DfailIfNoTests=false \
  -Dmaven.gitcommitid.skip=true

Result: 1 test passed.

PYSPARK_PYTHON="$(command -v python3.12)" \
PYSPARK_DRIVER_PYTHON="$(command -v python3.12)" \
./mvnw test \
  -pl spark/interpreter \
  --am \
  -Pspark-3.5 \
  -Pspark-scala-2.12 \
  -Dtest=PySparkInterpreterTest#testPySpark \
  -Dsurefire.failIfNoSpecifiedTests=false \
  -Dmaven.gitcommitid.skip=true

Results:

• PySparkInterpreterTest#testPySpark passed.
• Existing ScalaTest suite: 18 tests passed.
• z.show(DataFrame) was exercised successfully.

./mvnw package \
  -pl spark/interpreter \
  --am \
  -Pspark-3.5 \
  -Pspark-scala-2.12 \
  -DskipTests \
  -Dmaven.gitcommitid.skip=true

Result: 12-module reactor build succeeded.

./mvnw package \
  -pl flink/flink-scala-2.12 \
  --am \
  -Pflink-1.20 \
  -DskipTests \
  -Dmaven.gitcommitid.skip=true

Result: 13-module reactor build succeeded.

The generated Spark and Flink interpreter JARs were also verified to contain the shared context resource and the corresponding classic and IPython bootstrap resources.

git diff --check also passes.

Screenshots (if appropriate)

Not applicable. This PR does not change the user interface.

Questions

• Do the license files need to be updated? No.
• Are there breaking changes for older versions? No. The existing IPython context names remain available as compatibility aliases.
• Does this need documentation? No. There are no user-facing behavior or configuration changes.

[ParkGyeongTae]

LGTM — clean fix for the long-standing PySpark/PyFlink ZeppelinContext duplication TODO. Backend-specific show() logic and compat aliases are preserved, and there's test coverage for the alias contract. One non-blocking nit inline.

[ParkGyeongTae]

nit: PySparkZeppelinContext isn't imported here on purpose — IPythonInterpreter already execs zeppelin_context.py into this same kernel session first. Worth a one-line comment so it's not mistaken for a missing import.

[ParkGyeongTae]

nit: same as the PySpark side — PyFlinkZeppelinContext is only in scope because zeppelin_context.py was already exec'd into this kernel session.

[ParkGyeongTae]

Merged into master (e1d96d6).