Add less_than()/greater_than() Fix functions. (#650)

Author: blackwinter

metafix/src/main/java/org/metafacture/metafix/FixConditional.java

@@ -182,6 +182,19 @@ public boolean test(final Metafix metafix, final Record record, final List<Strin
         public boolean test(final Metafix metafix, final Record record, final List<String> params, final Map<String, String> options) {
             return testConditional(params, MATCHES);
         }
+    },
+
+    greater_than {
+        @Override
+        public boolean test(final Metafix metafix, final Record record, final List<String> params, final Map<String, String> options) {
+            return testConditional(record, params, ALL, GREATER_THAN);
+        }
+    },
+    less_than {
+        @Override
+        public boolean test(final Metafix metafix, final Record record, final List<String> params, final Map<String, String> options) {
+            return testConditional(record, params, ALL, LESS_THAN);
+        }
     }
 
 }

metafix/src/main/java/org/metafacture/metafix/api/FixPredicate.java

@@ -40,15 +40,10 @@ public interface FixPredicate {
     Predicate<String> IS_TRUE = s -> "true".equals(s) || "1".equals(s);
     Predicate<String> IS_FALSE = s -> "false".equals(s) || "0".equals(s);
 
-    Predicate<String> IS_NUMBER = s -> {
-        try {
-            new BigDecimal(s);
-            return true;
-        }
-        catch (final NumberFormatException e) {
-            return false;
-        }
-    };
+    Predicate<String> IS_NUMBER = s -> testNumberConditional(s, x -> true);
+
+    BiPredicate<String, String> GREATER_THAN = (s, t) -> testNumberConditional(s, x -> testNumberConditional(t, y -> x.compareTo(y) > 0));
+    BiPredicate<String, String> LESS_THAN = (s, t) -> testNumberConditional(s, x -> testNumberConditional(t, y -> x.compareTo(y) < 0));
 
     Predicate<Value> IS_EMPTY = v -> v.extractType((m, c) -> m
             .ifArray(a -> c.accept(a.isEmpty()))
@@ -88,4 +83,14 @@ default boolean testStringConditional(final Record record, final List<String> pa
         ));
     }
 
+    static boolean testNumberConditional(final String string, final Predicate<BigDecimal> conditional) {
+        try {
+            final BigDecimal number = new BigDecimal(string);
+            return number != null && conditional.test(number);
+        }
+        catch (final NumberFormatException e) {
+            return false;
+        }
+    }
+
 }