diff --git a/src/main/java/be/cylab/java/wowa/training/SolutionDistance.java b/src/main/java/be/cylab/java/wowa/training/SolutionDistance.java
index 4592e3a3a4a8cee9031fa9f727f93a8fb5d75f4c..38ac0b3884da11ac1fc40872e73b92c7a0221c60 100644
--- a/src/main/java/be/cylab/java/wowa/training/SolutionDistance.java
+++ b/src/main/java/be/cylab/java/wowa/training/SolutionDistance.java
@@ -2,8 +2,6 @@ package be.cylab.java.wowa.training;
 
 //import info.debatty.java.aggregation.WOWA;
 
-import org.jetbrains.annotations.NotNull;
-
 import java.util.Arrays;
 import java.util.List;
 
@@ -74,7 +72,7 @@ public class SolutionDistance implements Comparable<SolutionDistance> {
      * @return
      */
     @Override
-    public int compareTo(@NotNull final SolutionDistance solution) {
+    public int compareTo(final SolutionDistance solution) {
         return this.getDistance() > solution.getDistance() ? -1 : this.getDistance() < solution.getDistance() ? 1 : 0;
     }
 
diff --git a/src/main/java/be/cylab/java/wowa/training/Trainer.java b/src/main/java/be/cylab/java/wowa/training/Trainer.java
index 278138d02578d66af577ba43c584c60767122e69..8af89449459de21c6beb5d1da52fd3dd4f0f49a6 100644
--- a/src/main/java/be/cylab/java/wowa/training/Trainer.java
+++ b/src/main/java/be/cylab/java/wowa/training/Trainer.java
@@ -1,6 +1,5 @@
 package be.cylab.java.wowa.training;
 
-import org.jetbrains.annotations.Contract;
 
 import java.util.ArrayList;
 import java.util.Collections;