Merge pull request #8 from magro/master

tonymorris · tonymorris · commit 7d366ef47aab · 2011-08-26T04:16:02.000-07:00
Add isNotNullOrEmpty to Strings.
diff --git a/core/src/main/java/fj/Ord.java b/core/src/main/java/fj/Ord.java
@@ -637,4 +637,25 @@ public Ordering f(final A a2) {
       }
     });
   }
+
+  /**
+   * An order instance that uses {@link Object#hashCode()} for computing the order.
+   *
+   * @return An order instance that is based on {@link Object#hashCode()}.
+   */
+  public static <A> Ord<A> hashOrd() {
+    return Ord.<A> ord(new F<A, F<A, Ordering>>() {
+      @Override
+      public F<A, Ordering> f(final A a) {
+        return new F<A, Ordering>() {
+          @Override
+          public Ordering f(final A a2) {
+            final int x = a.hashCode() - a2.hashCode();
+            return x < 0 ? Ordering.LT : x == 0 ? Ordering.EQ : Ordering.GT;
+          }
+        };
+      }
+    });
+  }
+
 }
diff --git a/core/src/main/java/fj/function/Strings.java b/core/src/main/java/fj/function/Strings.java
@@ -14,6 +14,16 @@ private Strings() {
     throw new UnsupportedOperationException();
   }
 
+  /**
+   * This function checks if a given String is neither <code>null</code> nor empty.
+   */
+  public static final F<String, Boolean> isNotNullOrEmpty = new F<String, Boolean>() {
+    @Override
+    public Boolean f(final String a) {
+      return a != null && a.length() > 0;
+    }
+  };
+
   /**
    * A curried version of {@link String#isEmpty()}.
    */
