diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/FieldSignature.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/FieldSignature.java
index 2083fca749..1477c68ff9 100644
--- a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/FieldSignature.java
+++ b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/FieldSignature.java
@@ -49,15 +49,11 @@ public final class FieldSignature extends Signature {
 
     @Override
     public boolean equals(Object o) {
-        if (o instanceof FieldSignature) {
-            FieldSignature f = (FieldSignature) o;
-            return super.equals(o) && f.isFinal == isFinal && f.isStatic == isStatic;
-        }
-        return false;
+        return this == o;
     }
 
     @Override
     public int hashCode() {
-        return super.hashCode() * 16 + (isStatic ? 1 : 0) * 32 + (isFinal ? 1 : 0);
+        return (isFinal ? 1 : 0) + super.hashCode() << 3 + (isStatic ? 1 : 0) << 1;
     }
 }
diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/OperationSignature.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/OperationSignature.java
index e456cf830e..5004bbaecb 100644
--- a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/OperationSignature.java
+++ b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/OperationSignature.java
@@ -69,13 +69,12 @@ public final class OperationSignature extends Signature {
 
     @Override
     public boolean equals(Object o) {
-        return o instanceof OperationSignature && super.equals(o) && role == ((OperationSignature) o).role
-            && isAbstract == ((OperationSignature) o).isAbstract;
+        return this == o;
     }
 
     @Override
     public int hashCode() {
-        return super.hashCode() * 2 + role.hashCode() * 4 + (isAbstract ? 1 : 0);
+        return (isAbstract ? 1 : 0) + super.hashCode() << 1 + role.hashCode() << 2;
     }
 
     /**
@@ -102,6 +101,7 @@ public final class OperationSignature extends Signature {
             }
         }
 
+        // TODO:cf clean that up
         private static boolean isGetterOrSetter(ASTMethodDeclaration node) {
             String name = node.getName();
             if (NAME_PATTERN.matcher(name).matches()) {
diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/Signature.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/Signature.java
index 2cf2873d70..d363dcc849 100644
--- a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/Signature.java
+++ b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/oom/signature/Signature.java
@@ -26,7 +26,7 @@ public abstract class Signature {
 
     @Override
     public int hashCode() {
-        return visibility.hashCode() * 2;
+        return visibility.hashCode();
     }
 
     /**
diff --git a/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/oom/metrics/xml/NcssTest.xml b/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/oom/metrics/xml/NcssTest.xml
index 0dd9d3d71d..8ba0a6b399 100644
--- a/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/oom/metrics/xml/NcssTest.xml
+++ b/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/oom/metrics/xml/NcssTest.xml
@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <test-data>
+    <!-- All these tests have been tested against JavaNCSS -->
+
 
     <code-fragment id="full-example">
         <![CDATA[