[SPARK-8525][MLLIB] fix LabeledPoint parser when there is a whitespace on specific position

Author: fe2s

mllib/src/main/scala/org/apache/spark/mllib/util/NumericParser.scala

@@ -19,6 +19,8 @@ package org.apache.spark.mllib.util
 
 import java.util.StringTokenizer
 
+import org.apache.commons.lang.StringUtils.isBlank
+
 import scala.collection.mutable.{ArrayBuilder, ListBuffer}
 
 import org.apache.spark.SparkException
@@ -98,6 +100,8 @@ private[mllib] object NumericParser {
         }
       } else if (token == ")") {
         parsing = false
+      } else if (isBlank(token)){
+          // ignore whitespaces between delim chars, e.g. ", ["
       } else {
         // expecting a number
         items.append(parseDouble(token))

mllib/src/test/scala/org/apache/spark/mllib/regression/LabeledPointSuite.scala

@@ -31,6 +31,11 @@ class LabeledPointSuite extends SparkFunSuite {
     }
   }
 
+  test("parse labeled points with whitespaces") {
+    val point = LabeledPoint.parse("(0.0, [1.0, 2.0])")
+    assert(point === LabeledPoint(0.0, Vectors.dense(1.0, 2.0)))
+  }
+
   test("parse labeled points with v0.9 format") {
     val point = LabeledPoint.parse("1.0,1.0 0.0 -2.0")
     assert(point === LabeledPoint(1.0, Vectors.dense(1.0, 0.0, -2.0)))

mllib/src/test/scala/org/apache/spark/mllib/util/NumericParserSuite.scala

@@ -37,4 +37,11 @@ class NumericParserSuite extends SparkFunSuite {
       }
     }
   }
+
+  test("parser with whitespaces") {
+    val s = "(0.0, [1.0, 2.0])"
+    val parsed = NumericParser.parse(s).asInstanceOf[Seq[_]]
+    assert(parsed(0).asInstanceOf[Double] === 0.0)
+    assert(parsed(1).asInstanceOf[Array[Double]] === Array(1.0, 2.0))
+  }
 }