[SPARK-14565][ML] RandomForest should use parseInt and parseDouble for feature subset size instead of regexes

## What changes were proposed in this pull request?

This fix tries to change RandomForest's supported strategies from using regexes to using parseInt and
parseDouble, for the purpose of robustness and maintainability.

## How was this patch tested?

Existing tests passed.

Author: Yong Tang <yong.tang.github@outlook.com>

Closes #12360 from yongtang/SPARK-14565.

1 files changed, 2 insertions, 2 deletions

diff --git a/mllib/src/test/scala/org/apache/spark/ml/tree/impl/RandomForestSuite.scala b/mllib/src/test/scala/org/apache/spark/ml/tree/impl/RandomForestSuite.scala
index 6db9ce150d..1719f9fab5 100644
--- a/mllib/src/test/scala/org/apache/spark/ml/tree/impl/RandomForestSuite.scala
+++ b/mllib/src/test/scala/org/apache/spark/ml/tree/impl/RandomForestSuite.scala
@@ -440,7 +440,7 @@ class RandomForestSuite extends SparkFunSuite with MLlibTestSparkContext {
 
     val invalidStrategies = Array("-.1", "-.10", "-0.10", ".0", "0.0", "1.1", "0")
     for (invalidStrategy <- invalidStrategies) {
-      intercept[MatchError]{
+      intercept[IllegalArgumentException]{
         val metadata =
           DecisionTreeMetadata.buildMetadata(rdd, strategy, numTrees = 1, invalidStrategy)
       }
@@ -463,7 +463,7 @@ class RandomForestSuite extends SparkFunSuite with MLlibTestSparkContext {
       checkFeatureSubsetStrategy(numTrees = 2, strategy, expected)
     }
     for (invalidStrategy <- invalidStrategies) {
-      intercept[MatchError]{
+      intercept[IllegalArgumentException]{
         val metadata =
           DecisionTreeMetadata.buildMetadata(rdd, strategy, numTrees = 2, invalidStrategy)
       }