v0.2.54..v0.2.55 changeset ProbabilityOfMatch.h

diff --git a/hoot-core/src/main/cpp/hoot/core/algorithms/ProbabilityOfMatch.h b/hoot-core/src/main/cpp/hoot/core/algorithms/ProbabilityOfMatch.h
index 1344d09..558717e 100644
--- a/hoot-core/src/main/cpp/hoot/core/algorithms/ProbabilityOfMatch.h
+++ b/hoot-core/src/main/cpp/hoot/core/algorithms/ProbabilityOfMatch.h
@@ -22,7 +22,7 @@
  * This will properly maintain the copyright information. DigitalGlobe
  * copyrights will be updated automatically.
  *
- * @copyright Copyright (C) 2015, 2016, 2017, 2018, 2019 DigitalGlobe (http://www.digitalglobe.com/)
+ * @copyright Copyright (C) 2015, 2016, 2017, 2018, 2019, 2020 DigitalGlobe (http://www.digitalglobe.com/)
  */
 
 #ifndef PROBABILITYOFMATCH_H
@@ -68,11 +68,15 @@ public:
 
 private:
 
-  ProbabilityOfMatch();
-
-  static std::shared_ptr<ProbabilityOfMatch> _theInstance;
   double _parallelExp;
   double _dMax;
+
+  ProbabilityOfMatch();
+  /** Default destructor */
+  ~ProbabilityOfMatch() = default;
+  /** Delete copy constructor and assignment operator */
+  ProbabilityOfMatch(const ProbabilityOfMatch&) = delete;
+  ProbabilityOfMatch& operator=(const ProbabilityOfMatch&) = delete;
 };
 
 }