Scala & Spark: Limitations of IntelliJ IDE's "Evaluate Expression" window -


i ran across unexpected behaviour in intelli j ideas (v.2016.2) "evaluate expression" window:

while works, both compiled code , using "evaluate expression" window

  val df1 = spark.read.json("/examples/src/main/resources/people.json")   df1.columns.foreach(println) // outputs "age" , "name" console 

another dataset[row] (dataframe) involves columns generated expressions works compiled code, while in "evaluate expression" window following exception displayed:

 com.intellij.debugger.engine.evaluation.evaluateexception:   type mismatch can't assign org.apache.spark.sql.dataset scala.runtime.objectref 

both dataframes of class class org.apache.spark.sql.dataset. according intelli js documentation limitations are:

  • a method can invoked within expression evaluation dialog if debugger has stopped @ breakpoint, has not been paused.
  • expression evaluation can "single-level". in other words, if intellij idea stops @ breakpoint within method called expression evaluation, cannot use expression evaluation feature again.
  • if method invoked within expression evaluation has breakpoint inside body, breakpoint ignored.

that apparently half truth.


Comments

Popular posts from this blog

aws api gateway - SerializationException in posting new Records via Dynamodb Proxy Service in API -

asp.net - Problems sending emails from forum -