diff --git a/core/src/main/java/org/springframework/plugin/core/OrderAwarePluginRegistry.java b/core/src/main/java/org/springframework/plugin/core/OrderAwarePluginRegistry.java
index 3ef969d..2cc6e04 100644
--- a/core/src/main/java/org/springframework/plugin/core/OrderAwarePluginRegistry.java
+++ b/core/src/main/java/org/springframework/plugin/core/OrderAwarePluginRegistry.java
@@ -21,7 +21,7 @@ import java.util.Comparator;
 import java.util.List;
 
 import org.springframework.core.annotation.AnnotationAwareOrderComparator;
-import org.springframework.util.comparator.InvertibleComparator;
+import org.springframework.util.Assert;
 
 /**
  * {@link PluginRegistry} implementation that be made aware of a certain ordering of {@link Plugin}s. By default it
@@ -42,10 +42,9 @@ public class OrderAwarePluginRegistry<T extends Plugin<S>, S> extends SimplePlug
 	/**
 	 * Comparator reverting the {@value #DEFAULT_COMPARATOR}.
 	 */
-	private static final Comparator<Object> DEFAULT_REVERSE_COMPARATOR = new InvertibleComparator<Object>(
-			DEFAULT_COMPARATOR, false);
+	private static final Comparator<Object> DEFAULT_REVERSE_COMPARATOR = DEFAULT_COMPARATOR.reversed();
 
-	private Comparator<? super T> comparator;
+	private final Comparator<? super T> comparator;
 
 	/**
 	 * Creates a new {@link OrderAwarePluginRegistry} with the given {@link Plugin}s and {@link Comparator}.
@@ -55,11 +54,13 @@ public class OrderAwarePluginRegistry<T extends Plugin<S>, S> extends SimplePlug
 	 * @param comparator the {@link Comparator} to be used for ordering the {@link Plugin}s or {@literal null} if the
 	 *          {@code #DEFAULT_COMPARATOR} shall be used.
 	 */
-	@SuppressWarnings("unchecked")
 	protected OrderAwarePluginRegistry(List<? extends T> plugins, Comparator<? super T> comparator) {
 
 		super(plugins);
-		this.comparator = (Comparator<? super T>) (comparator == null ? DEFAULT_COMPARATOR : comparator);
+
+		Assert.notNull(comparator, "Comparator must not be null!");
+
+		this.comparator = comparator;
 	}
 
 	/**
@@ -68,23 +69,27 @@ public class OrderAwarePluginRegistry<T extends Plugin<S>, S> extends SimplePlug
 	 * @return
 	 */
 	public static <S, T extends Plugin<S>> OrderAwarePluginRegistry<T, S> create() {
-		return create(Collections.<T> emptyList());
+		return create(Collections.emptyList());
 	}
 
 	/**
 	 * Creates a new {@link OrderAwarePluginRegistry} using the given {@link Comparator} for ordering contained
 	 * {@link Plugin}s.
 	 * 
+	 * @param comparator must not be {@literal null}.
 	 * @return
 	 */
 	public static <S, T extends Plugin<S>> OrderAwarePluginRegistry<T, S> create(Comparator<? super T> comparator) {
-		return create(Collections.<T> emptyList(), comparator);
+
+		Assert.notNull(comparator, "Comparator must not be null!");
+
+		return create(Collections.emptyList(), comparator);
 	}
 
 	/**
 	 * Creates a new {@link OrderAwarePluginRegistry} with the given plugins.
 	 * 
-	 * @param plugins
+	 * @param plugins must not be {@literal null}.
 	 * @return
 	 */
 	public static <S, T extends Plugin<S>> OrderAwarePluginRegistry<T, S> create(List<? extends T> plugins) {
@@ -92,9 +97,10 @@ public class OrderAwarePluginRegistry<T extends Plugin<S>, S> extends SimplePlug
 	}
 
 	/**
-	 * Creates a new {@link OrderAwarePluginRegistry} with the given plugins and the order of the plugins reverted.
+	 * Creates a new {@link OrderAwarePluginRegistry} with the given {@link Plugin}s and the order of the {@link Plugin}s
+	 * reverted.
 	 * 
-	 * @param plugins
+	 * @param plugins must not be {@literal null}.
 	 * @return
 	 */
 	public static <S, T extends Plugin<S>> OrderAwarePluginRegistry<T, S> createReverse(List<? extends T> plugins) {
@@ -109,7 +115,11 @@ public class OrderAwarePluginRegistry<T extends Plugin<S>, S> extends SimplePlug
 	 */
 	public static <S, T extends Plugin<S>> OrderAwarePluginRegistry<T, S> create(List<? extends T> plugins,
 			Comparator<? super T> comparator) {
-		return new OrderAwarePluginRegistry<T, S>(plugins, comparator);
+
+		Assert.notNull(plugins, "Plugins must not be null!");
+		Assert.notNull(comparator, "Comparator must not be null!");
+
+		return new OrderAwarePluginRegistry<>(plugins, comparator);
 	}
 
 	/* 
@@ -129,10 +139,9 @@ public class OrderAwarePluginRegistry<T extends Plugin<S>, S> extends SimplePlug
 	 * 
 	 * @return
 	 */
-	@SuppressWarnings({ "unchecked", "rawtypes" })
 	public OrderAwarePluginRegistry<T, S> reverse() {
 
-		ArrayList<T> copy = new ArrayList<T>(getPlugins());
-		return create(copy, new InvertibleComparator(comparator, false));
+		List<T> copy = new ArrayList<>(getPlugins());
+		return create(copy, comparator.reversed());
 	}
 }
diff --git a/core/src/test/java/org/springframework/plugin/core/support/BeanListFactoryBeanUnitTest.java b/core/src/test/java/org/springframework/plugin/core/support/BeanListFactoryBeanUnitTest.java
index 4725517..4d35316 100644
--- a/core/src/test/java/org/springframework/plugin/core/support/BeanListFactoryBeanUnitTest.java
+++ b/core/src/test/java/org/springframework/plugin/core/support/BeanListFactoryBeanUnitTest.java
@@ -55,8 +55,8 @@ public class BeanListFactoryBeanUnitTest {
 	public void regardsOrderOfBeans() throws Exception {
 
 		// They shall be switched in the result.
-		Ordered first = getOrdered(5);
-		Ordered second = getOrdered(0);
+		Ordered first = () -> 5;
+		Ordered second = () -> 0;
 
 		when(context.getBeanNamesForType(Ordered.class, false, false)).thenReturn(new String[] { "first", "second" });
 		when(context.getType(any(String.class))).thenReturn((Class) Ordered.class);
@@ -86,24 +86,6 @@ public class BeanListFactoryBeanUnitTest {
 
 	@SuppressWarnings("unchecked")
 	private <T> List<T> type(Object list) {
-
 		return (List<T>) list;
 	}
-
-	/**
-	 * Returns an {@link Ordered} with the given order.
-	 * 
-	 * @param order
-	 * @return
-	 */
-	public Ordered getOrdered(final int order) {
-
-		return new Ordered() {
-
-			public int getOrder() {
-
-				return order;
-			}
-		};
-	}
 }