diff --git a/src/main/java/org/apache/commons/math/transform/FastCosineTransformer.java b/src/main/java/org/apache/commons/math/transform/FastCosineTransformer.java
index d460f8250..9ded318d0 100644
--- a/src/main/java/org/apache/commons/math/transform/FastCosineTransformer.java
+++ b/src/main/java/org/apache/commons/math/transform/FastCosineTransformer.java
@@ -58,7 +58,7 @@ public class FastCosineTransformer implements RealTransformer {
      * @see #create()
      * @see #createOrthogonal()
      */
-    public FastCosineTransformer(final boolean orthogonal) {
+    private FastCosineTransformer(final boolean orthogonal) {
         this.orthogonal = orthogonal;
     }