Moved from gradle to sbt.

1 files changed, 18 insertions, 0 deletions

diff --git a/core/src/main/scala/com/rockymadden/stringmetric/similarity/HammingMetric.scala b/core/src/main/scala/com/rockymadden/stringmetric/similarity/HammingMetric.scala
new file mode 100755
index 0000000..4a90f32
--- /dev/null
+++ b/core/src/main/scala/com/rockymadden/stringmetric/similarity/HammingMetric.scala
@@ -0,0 +1,18 @@
+package com.rockymadden.stringmetric.similarity
+
+import com.rockymadden.stringmetric.Metric.StringMetric
+
+case object HammingMetric extends StringMetric[Int] {
+	import com.rockymadden.stringmetric.CompareTuple
+
+	override def compare(a: Array[Char], b: Array[Char]): Option[Int] =
+		if (a.length == 0 || b.length == 0 || a.length != b.length) None
+		else if (a.sameElements(b)) Some(0)
+		else Some(hamming(a, b))
+
+	override def compare(a: String, b: String): Option[Int] = compare(a.toCharArray, b.toCharArray)
+
+	private val hamming: (CompareTuple[Char] => Int) = (ct) =>
+		if (ct._1.length == 0) 0
+		else ct._1.zip(ct._2).count(t => t._1 != t._2)
+}