cannot capture NumberFormatException in a unit test - scala

Question

i have a unit test which have to fail at purpose, but I cannot capture it, so it is weird.
This is how it looks the csv file:
curva;clase;divisa;rw
AED_FXDEP;OIS;AED;240,1000
ARS :Std;6m;ARS;240
AUD_CALMNY_DISC;OIS;AUD;169.7056275
AUD_DEPO_BBSW;6m;AUD;169.7056275
AUD_DEPO_BBSW;6m;AUD;
And this is the content of the json schema file:
{"type" : "struct","fields" : [ {"name" : "curve","type" : "string","nullable" : false}, {"name":"class", "type":"string", "nullable":false}, {"name":"currency", "type":"string", "nullable":false}, {"name":"rw", "type":"string","nullable":false} ]
I think it is self explainable, the last line of the csv has an empty field and that is not permitted, the exception is clear, NumberFormatException because you can create a number with an empty value. I want to catch the exception in the unit test, why I can't reach it?
This is the code that provokes the exception:
try{
val validateGenericFile : Boolean = CSVtoParquet.validateGenericCSV(pathCSVWithHeaderWithErrors,
pathCurvasJsonSchemaWithDecimal,
_nullValue,
_delimiter,
sc,
sqlContext)
//never reach!
Assert.assertTrue(validateGenericFile)
} catch {
case e:NumberFormatException => Assert.assertTrue("ERROR! " + e.getLocalizedMessage,false)
case ex:Exception => Assert.assertTrue("ERROR! " + ex.getLocalizedMessage,false)
} finally {
println("Done testValidateInputFilesFRTBSTDES436_WithErrors!")
}
the method validateGenericCSV looks like:
val myDfWithCustomSchema = _sqlContext.read.format("com.databricks.spark.csv").
option("header", "true").
option("delimiter", _delimiter).
option("nullValue", _nullValue).
option("mode","FAILFAST").
schema(mySchemaStructType).
load(fileToReview)
var finallyCorrect : Boolean = true
var contLinesProcessed = 1
try{
//this line provokes the exception!
val myArray = myDfWithCustomSchema.collect
var contElementosJson = 0
var isTheLineCorrect: Boolean = true
myArray.foreach { elem =>
println("Processing line with content: " + elem)
for (myElem <- myList) {
val actualType = myElem.`type`
val actualName = myElem.name
val actualNullable = myElem.nullable
if (contElementosJson == myList.size) {
contElementosJson = 0
}
if (actualType == "string") {
val theField = elem.getString(contElementosJson)
val validatingField: Boolean = theField.isInstanceOf[String]
isTheLineCorrect = validatingField && !((theField == "" || theField == null) && !actualNullable)
contElementosJson += 1
if (!isTheLineCorrect){
finallyCorrect=false
println("ATTENTION! an empty string chain. " + "Check this field " + actualName + " in the csv file, which should be a " + actualType + " according with the json schema file, can be nullable? " + actualNullable + " isTheLineCorrect? " + isTheLineCorrect)
}
} else if (actualType == "integer") {
val theField = elem.get(contElementosJson)
val validatingField: Boolean = theField.isInstanceOf[Integer]
isTheLineCorrect = validatingField && !((theField == "" || theField == null) && !actualNullable)
contElementosJson += 1
if (!isTheLineCorrect){
finallyCorrect=false
println("ATTENTION! an empty string chain. " + "Check this field " + actualName + " in the csv file, which should be a " + actualType + " according with the json schema file, can be nullable? " + actualNullable + " isTheLineCorrect? " + isTheLineCorrect)
}
} else if (actualType.startsWith("decimal")) {
val theField = elem.get(contElementosJson)
val validatingField: Boolean = theField.isInstanceOf[java.math.BigDecimal]
isTheLineCorrect = validatingField && !((theField == "" || theField == null) && !actualNullable)
contElementosJson += 1
if (!isTheLineCorrect){
finallyCorrect=false
println("ATTENTION! an empty string chain. " + "Check this field " + actualName + " in the csv file, which should be a " + actualType + " according with the json schema file, can be nullable? " + actualNullable + " isTheLineCorrect? " + isTheLineCorrect)
}
} else {
println("Attention! se está intentando procesar una columna del tipo " + actualType + " que no está prevista procesar. Comprobar.")
}
} //for
contLinesProcessed += 1
} //foreach))
} catch {
//NEVER REACHED! why????
case e:NumberFormatException => throw e
case ex:Exception => throw ex
}
Why the NumberFormatException is never reached within in validateGenericCSV method?
UPDATE
i have modified these lines:
case e:NumberFormatException => Assert.assertTrue("ERROR! " + e.getLocalizedMessage,true)
case ex:Exception => Assert.assertTrue("ERROR! " + ex.getLocalizedMessage,true)
for these lines:
case e:NumberFormatException => Assert.assertTrue("ERROR! " + e.getLocalizedMessage,false)
case ex:Exception => Assert.assertTrue("ERROR! " + ex.getLocalizedMessage,false)
The same error, my problem is that I cannot reach to the catch sentences when the exception happens!
Thank you

Answer 1

When inspecting the stack trace, we can see the following:
ERROR! Job aborted due to stage failure: Task 1 in stage 1.0 failed 1 times, most recent failure: Lost task 1.0 in stage 1.0 (TID 2, localhost): java.lang.NumberFormatException
Spark is a distributed computing framework. The NumberFormatException is taking place remotely at one of the executors while processing a task. Spark gets a TaskFailure from that executor and propagates the exception wrapped in a org.apache.spark.SparkException to the action that triggered the materialization of the computation: the .collect() method in this specific case.
If we would like to get the reason behind the failure, we can use ex.getCause.
In practical terms we will have something like this snippet:
catch {
case ex:Exception if ex.getCause.getClass == classOf[NumberFormatException] => Assert.fail("Number parsing failed" + e.getLocalizedMessage)
case ex:Exception => Assert.fail(...)
}

Answer 2

The test won't fail because Assert.assertTrue(...,true) does not fail. assertTrue fails if the second parameter is false but not when it's true.