diff --git a/app/src/test/java/info/nightscout/utils/JsonHelperTest.java b/app/src/test/java/info/nightscout/utils/JsonHelperTest.java
new file mode 100644
index 0000000000..3f5f8fd6e7
--- /dev/null
+++ b/app/src/test/java/info/nightscout/utils/JsonHelperTest.java
@@ -0,0 +1,29 @@
+package info.nightscout.utils;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ * Created by mike on 12.03.2018.
+ */
+
+public class JsonHelperTest {
+
+    String jsonString = "{\"d\":\"3.0\",\"i\":\"4\",\"s\":\"5\"}";
+
+    @Test
+    public void runTest() throws JSONException {
+        JSONObject object = new JSONObject(jsonString);
+        assertEquals(null, JsonHelper.safeGetString(object, "notexisting"));
+        assertEquals("5", JsonHelper.safeGetString(object, "s"));
+
+        assertEquals(0.0d, JsonHelper.safeGetDouble(object, "notexisting"), 0.0d);
+        assertEquals(3.0d, JsonHelper.safeGetDouble(object, "d"), 0.000001d);
+
+        assertEquals(0, JsonHelper.safeGetInt(object, "notexisting"));
+        assertEquals(4, JsonHelper.safeGetInt(object, "i"));
+    }
+}