Merge pull request searchbox-io#391 from SethAbrams/fix-aggregation-l…

…ogic-inconsistency

Fix aggregation logic inconsistency

jest-common/src/main/java/io/searchbox/core/search/aggregation/CardinalityAggregation.java

@@ -17,7 +17,9 @@ public class CardinalityAggregation extends MetricAggregation {
 
     public CardinalityAggregation(String name, JsonObject cardinalityAggregation) {
         super(name, cardinalityAggregation);
-        cardinality = cardinalityAggregation.get(String.valueOf(VALUE)).getAsLong();
+        if(cardinalityAggregation.has(String.valueOf(VALUE)) && !cardinalityAggregation.get(String.valueOf(VALUE)).isJsonNull()) {
+            cardinality = cardinalityAggregation.get(String.valueOf(VALUE)).getAsLong();
+        }
     }
 
     /**

jest-common/src/test/java/io/searchbox/search/aggregation/CardinalityAggregationTest.java

@@ -0,0 +1,41 @@
+package io.searchbox.search.aggregation;
+
+import com.google.gson.JsonObject;
+import io.searchbox.core.search.aggregation.CardinalityAggregation;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+
+public class CardinalityAggregationTest {
+    @Test
+    public void givenMissingValueProperty_cardinalityAggregationConstructor_doesNotAssignToCardinalityField() {
+        JsonObject cardinalityAggregationJson = new JsonObject();
+        cardinalityAggregationJson.addProperty("notValueField", "hi");
+        cardinalityAggregationJson.addProperty("anotherField", "hello");
+        CardinalityAggregation cardinalityAggregation = new CardinalityAggregation("aggName", cardinalityAggregationJson);
+        assertNull("Cardinality field should default to null since value is unassigned", cardinalityAggregation.getCardinality());
+    }
+
+    @Test
+    public void givenNullValueProperty_cardinalityAggregationConstructor_doesNotAssignToCardinalityField() {
+        JsonObject cardinalityAggregationJson = new JsonObject();
+        cardinalityAggregationJson.addProperty("notValueField", "hi");
+        cardinalityAggregationJson.addProperty("anotherField", "hello");
+        String nullString = null;
+        cardinalityAggregationJson.addProperty("value", nullString);
+        CardinalityAggregation cardinalityAggregation = new CardinalityAggregation("aggName", cardinalityAggregationJson);
+        assertNull("Cardinality field should default to null since value is null", cardinalityAggregation.getCardinality());
+    }
+
+    @Test
+    public void givenNonNullValueProperty_cardinalityAggregationConstructor_assignsToCardinalityField() {
+        JsonObject cardinalityAggregationJson = new JsonObject();
+        cardinalityAggregationJson.addProperty("notValueField", "hi");
+        cardinalityAggregationJson.addProperty("anotherField", "hello");
+        Long setValue = 100L;
+        cardinalityAggregationJson.addProperty("value", setValue);
+        CardinalityAggregation cardinalityAggregation = new CardinalityAggregation("aggName", cardinalityAggregationJson);
+        assertEquals(setValue, cardinalityAggregation.getCardinality());
+    }
+}