DATACMNS-888 - Added dedicated Sort type to be able to express directions for revisions.

Introduced dedicated RevisionSort property that allows to define the sort order independent of the revision property to be used.

Introduced methods to find out whether a Sort is descending or ascending to avoid having to refer to the enum.

src/main/java/org/springframework/data/domain/Sort.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2008-2014 the original author or authors.
+ * Copyright 2008-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -196,6 +196,26 @@ public class Sort implements Iterable<org.springframework.data.domain.Sort.Order
 
 		ASC, DESC;
 
+		/**
+		 * Returns whether the direction is ascending.
+		 * 
+		 * @return
+		 * @since 1.13
+		 */
+		public boolean isAscending() {
+			return this.equals(ASC);
+		}
+
+		/**
+		 * Returns whether the direction is descending.
+		 * 
+		 * @return
+		 * @since 1.13
+		 */
+		public boolean isDescending() {
+			return this.equals(DESC);
+		}
+
 		/**
 		 * Returns the {@link Direction} enum for the given {@link String} value.
 		 * 
@@ -350,7 +370,17 @@ public class Sort implements Iterable<org.springframework.data.domain.Sort.Order
 		 * @return
 		 */
 		public boolean isAscending() {
-			return this.direction.equals(Direction.ASC);
+			return this.direction.isAscending();
+		}
+
+		/**
+		 * Returns whether sorting for this property shall be descending.
+		 * 
+		 * @return
+		 * @since 1.13
+		 */
+		public boolean isDescending() {
+			return this.direction.isDescending();
 		}
 
 		/**