Standardize static util class constructor guard

src/main/java/com/speedment/util/Beans.java

@@ -27,9 +27,16 @@
  *
  * @author pemi
  */
-public class Beans {
-
+public class Beans implements PureStaticMethods {
+
+    /**
+     * This class contains only static methods and thus, no instance shall be
+     * created.
+     *
+     * @see PureStaticMethods#instanceNotAllowed()
+     */
     private Beans() {
+        instanceNotAllowed();
     }
 
     public static <P, T> T with(final T thizz, final P item, final Consumer<P> consumer) {

src/main/java/com/speedment/util/Cast.java

@@ -22,9 +22,17 @@
  *
  * @author pemi
  */
-public final class Cast {
+public final class Cast implements PureStaticMethods {
 
-    private Cast() {}
+    /**
+     * This class contains only static methods and thus, no instance shall be
+     * created.
+     *
+     * @see PureStaticMethods#instanceNotAllowed()
+     */
+    private Cast() {
+        instanceNotAllowed();
+    }
 
     public static <T> Optional<T> cast(Object o, Class<T> clazz) {
         if (clazz.isAssignableFrom(o.getClass())) {

src/main/java/com/speedment/util/CharSequences.java

@@ -20,9 +20,16 @@
  *
  * @author pemi
  */
-public class CharSequences {
+public class CharSequences implements PureStaticMethods {
 
+    /**
+     * This class contains only static methods and thus, no instance shall be
+     * created.
+     *
+     * @see PureStaticMethods#instanceNotAllowed()
+     */
     private CharSequences() {
+        instanceNotAllowed();
     }
 
     public static final int INDEX_NOT_FOUND = -1;

src/main/java/com/speedment/util/LongUtil.java

@@ -25,9 +25,16 @@
  *
  * @author pemi
  */
-public class LongUtil {
+public class LongUtil implements PureStaticMethods {
 
+    /**
+     * This class contains only static methods and thus, no instance shall be
+     * created.
+     *
+     * @see PureStaticMethods#instanceNotAllowed()
+     */
     private LongUtil() {
+        instanceNotAllowed();
     }
 
     @SuppressWarnings("unchecked")

src/main/java/com/speedment/util/Maps.java

@@ -26,7 +26,17 @@
  *
  * @author pemi
  */
-public class Maps {
+public class Maps implements PureStaticMethods {
+
+    /**
+     * This class contains only static methods and thus, no instance shall be
+     * created.
+     *
+     * @see PureStaticMethods#instanceNotAllowed()
+     */
+    private Maps() {
+        instanceNotAllowed();
+    }
 
     public static <K, V> Map.Entry<? extends K, ? extends V> entry(K key, V value) {
         return new AbstractMap.SimpleEntry<>(key, value);

src/main/java/com/speedment/util/Paths.java

@@ -22,7 +22,18 @@
  *
  * @author Emil Forslund
  */
-public class Paths {
+public class Paths implements PureStaticMethods {
+
+    /**
+     * This class contains only static methods and thus, no instance shall be
+     * created.
+     *
+     * @see PureStaticMethods#instanceNotAllowed()
+     */
+    private Paths() {
+        instanceNotAllowed();
+    }
+
     public static String toString(Path path) {
         return path.toString().replace("\\", "/");
     }

src/main/java/com/speedment/util/PureStaticMethods.java

@@ -0,0 +1,20 @@
+package com.speedment.util;
+
+/**
+ * Support interface for classes that only contains static methods. This
+ * interface can for example be used for various "Util" classes.
+ *
+ * @author pemi
+ */
+public interface PureStaticMethods {
+
+    /**
+     * Support method that can be used in constructors to throw an
+     * {@Code UnsupportedOperationException} if someone is trying to create an
+     * instance of the class.
+     */
+    default void instanceNotAllowed() {
+        throw new UnsupportedOperationException("It is not allowed to create instances of the " + getClass().getName() + " class");
+    }
+
+}

src/main/java/com/speedment/util/Trees.java

@@ -27,9 +27,10 @@
  *
  * @author pemi
  */
-public class Trees {
+public class Trees implements PureStaticMethods {
 
-    public Trees() {
+    private Trees() {
+        instanceNotAllowed();
     }
 
     public static enum WalkingOrder {

src/main/java/com/speedment/util/analytics/AnalyticsUtil.java

@@ -16,25 +16,34 @@
  */
 package com.speedment.util.analytics;
 
+import com.speedment.util.PureStaticMethods;
+
 /**
  *
  * @author pemi
  */
-public class AnalyticsUtil {
-    
+public class AnalyticsUtil implements PureStaticMethods {
+
     private static final String TRACKING_CODE = "UA-54384165-1";
-
+
+    /**
+     * This class contains only static methods and thus, no instance shall be
+     * created.
+     *
+     * @see PureStaticMethods#instanceNotAllowed()
+     */
     private AnalyticsUtil() {
+        instanceNotAllowed();
     }
-    
+
     public static void notify(final FocusPoint focusPoint) {
         final JGoogleAnalyticsTracker tracker = new JGoogleAnalyticsTracker(TRACKING_CODE);
         tracker.setLoggingAdapter(new LoggingAdapterImpl());
         tracker.trackAsynchronously(focusPoint);
     }
-    
+
     public static void notify(final String focusPointName) {
         notify(new FocusPoint(focusPointName));
     }
-    
+
 }