Add import

Author: geniejhang

epics-vtype/vtype-json/src/main/java/org/epics/vtype/json/JsonVTypeBuilder.java

@@ -12,6 +12,7 @@
 import javax.json.Json;
 import javax.json.JsonArrayBuilder;
 import javax.json.JsonObject;
+import javax.json.JsonBuilderFactory;
 import javax.json.JsonObjectBuilder;
 import javax.json.JsonValue;
 import static org.epics.vtype.json.JsonArrays.*;