Moved from gradle to sbt.

1 files changed, 23 insertions, 0 deletions

diff --git a/core/src/main/scala/com/rockymadden/stringmetric/similarity/JaroWinklerMetric.scala b/core/src/main/scala/com/rockymadden/stringmetric/similarity/JaroWinklerMetric.scala
new file mode 100755
index 0000000..e83f73f
--- /dev/null
+++ b/core/src/main/scala/com/rockymadden/stringmetric/similarity/JaroWinklerMetric.scala
@@ -0,0 +1,23 @@
+package com.rockymadden.stringmetric.similarity
+
+import com.rockymadden.stringmetric.Metric.StringMetric
+
+/**
+ * An implementation of the Jaro-Winkler metric. One differing detail in this implementation is that if a character is
+ * matched in string2, it cannot be matched upon again. This results in a more penalized distance in these scenarios
+ * (e.g. comparing henka and henkan distance is 0.9666 versus the typical 0.9722).
+ */
+case object JaroWinklerMetric extends StringMetric[Double] {
+	override def compare(a: Array[Char], b: Array[Char]): Option[Double] =
+		JaroMetric.compare(a, b).map {
+			case 0d => 0d
+			case 1d => 1d
+			case jaro => {
+				val prefix = a.zip(b).takeWhile(t => t._1 == t._2)
+
+				jaro + ((if (prefix.length <= 4) prefix.length else 4) * 0.1d * (1 - jaro))
+			}
+		}
+
+	override def compare(a: String, b: String): Option[Double] = compare(a.toCharArray, b.toCharArray)
+}