## What changes were proposed in this pull request?
add `SparseMatrix` class whick support pickler.
## How was this patch tested?
Existing test.
Author: WeichenXu <WeichenXu123@outlook.com>
Closes#14265 from WeichenXu123/picklable_py.
## What changes were proposed in this pull request?
Issue: Omitting the full classpath can cause problems when calling JVM methods or classes from pyspark.
This PR: Changed all uses of jvm.X in pyspark.ml and pyspark.mllib to use full classpath for X
## How was this patch tested?
Existing unit tests. Manual testing in an environment where this was an issue.
Author: Joseph K. Bradley <joseph@databricks.com>
Closes#14023 from jkbradley/SPARK-16348.
## What changes were proposed in this pull request?
Now we have PySpark picklers for new and old vector/matrix, individually. However, they are all implemented under `PythonMLlibAPI`. To separate spark.mllib from spark.ml, we should implement the picklers of new vector/matrix under `spark.ml.python` instead.
## How was this patch tested?
Existing tests.
Author: Liang-Chi Hsieh <simonh@tw.ibm.com>
Closes#13219 from viirya/pyspark-pickler-ml.
