diff --git a/offix/src/main/java/org/aerogear/offix/ConversionCheck.kt b/offix/src/main/java/org/aerogear/offix/ConversionCheck.kt
new file mode 100644
index 0000000..ff33627
--- /dev/null
+++ b/offix/src/main/java/org/aerogear/offix/ConversionCheck.kt
@@ -0,0 +1,13 @@
+package org.aerogear.offix
+
+import com.apollographql.apollo.api.OperationName
+
+object ConversionCheck{
+    fun checkStringisJson(s: String): Boolean {
+        return s.startsWith("{")&&s.endsWith("}")
+    }
+    fun operationNameExists(n: OperationName): Boolean{
+        return !n.name().isBlank()
+    }
+}
+
diff --git a/offix/src/main/java/org/aerogear/offix/persistence/Converters.kt b/offix/src/main/java/org/aerogear/offix/persistence/Converters.kt
index c618859..b185928 100644
--- a/offix/src/main/java/org/aerogear/offix/persistence/Converters.kt
+++ b/offix/src/main/java/org/aerogear/offix/persistence/Converters.kt
@@ -2,7 +2,9 @@ package org.aerogear.offix.persistence
 
 import android.arch.persistence.room.TypeConverter
 import com.apollographql.apollo.api.OperationName
+import org.aerogear.offix.ConversionCheck
 import org.json.JSONObject
+import java.lang.Exception
 
 /*
 Converters are used to serialise and de-serialise objects for storing and fetching from database.
@@ -16,13 +18,21 @@ class Converters {
 
     @TypeConverter
     fun OperationNameToString(name: OperationName): String {
-        return name.name()
+        if(ConversionCheck.operationNameExists(name)) {
+            return name.name()
+        } else {
+            throw Exception("EmptyOperationNameException")
+        }
     }
 
     @TypeConverter
     fun StringToJson(string: String): JSONObject {
-        val jsonObject = JSONObject(string)
-        return jsonObject
+        if(ConversionCheck.checkStringisJson(string)) {
+            val jsonObject = JSONObject(string)
+            return jsonObject
+        } else {
+            return JSONObject("{}")
+        }
     }
 
     @TypeConverter
diff --git a/offix/src/test/java/org/aerogear/offix/ExampleUnitTest.java b/offix/src/test/java/org/aerogear/offix/ExampleUnitTest.java
deleted file mode 100644
index 215e23c..0000000
--- a/offix/src/test/java/org/aerogear/offix/ExampleUnitTest.java
+++ /dev/null
@@ -1,17 +0,0 @@
-package org.aerogear.offix;
-
-import org.junit.Test;
-
-import static org.junit.Assert.*;
-
-/**
- * Example local unit test, which will execute on the development machine (host).
- *
- * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
- */
-public class ExampleUnitTest {
-    @Test
-    public void addition_isCorrect() {
-        assertEquals(4, 2 + 2);
-    }
-}
\ No newline at end of file
diff --git a/offix/src/test/java/org/aerogear/offix/ExampleUnitTest.kt b/offix/src/test/java/org/aerogear/offix/ExampleUnitTest.kt
new file mode 100644
index 0000000..393841c
--- /dev/null
+++ b/offix/src/test/java/org/aerogear/offix/ExampleUnitTest.kt
@@ -0,0 +1,34 @@
+package org.aerogear.offix
+
+import com.apollographql.apollo.api.OperationName
+import org.junit.Test
+
+import org.junit.Assert.*
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * @see [Testing documentation](http://d.android.com/tools/testing)
+ */
+class ExampleUnitTest {
+    @Test
+    fun addition_isCorrect() {
+        assertEquals(4, (2 + 2).toLong())
+    }
+    @Test
+    fun stringJsonTrue(){
+        assertTrue(ConversionCheck.checkStringisJson("{}"))
+    }
+    @Test
+    fun stringJsonFalse(){
+        assertFalse(ConversionCheck.checkStringisJson("sd"))
+    }
+    @Test
+    fun operationNameTrue(){
+        assertTrue(ConversionCheck.operationNameExists(OperationName { "testUser" }))
+    }
+    @Test
+    fun operationNameFalse(){
+        assertFalse(ConversionCheck.operationNameExists(OperationName { "" }))
+    }
+}
\ No newline at end of file
diff --git a/sample/src/test/java/org/aerogear/graphqlandroid/ExampleUnitTest.kt b/sample/src/test/java/org/aerogear/graphqlandroid/ExampleUnitTest.kt
index 12ff30b..eb517d7 100644
--- a/sample/src/test/java/org/aerogear/graphqlandroid/ExampleUnitTest.kt
+++ b/sample/src/test/java/org/aerogear/graphqlandroid/ExampleUnitTest.kt
@@ -14,4 +14,6 @@ class ExampleUnitTest {
     fun addition_isCorrect() {
         assertEquals(4, 2 + 2)
     }
+
+
 }