From 566e648294d620b44f107ac7a6e6e1621ea327bd Mon Sep 17 00:00:00 2001
From: Luke Sikina <lucas.skina@gmail.com>
Date: Thu, 29 Aug 2024 09:24:49 -0400
Subject: [PATCH] [CHORE] NPEs for timestamps

---
 .../processing/timeseries/TimeSeriesConversionService.java     | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/processing/src/main/java/edu/harvard/hms/dbmi/avillach/hpds/processing/timeseries/TimeSeriesConversionService.java b/processing/src/main/java/edu/harvard/hms/dbmi/avillach/hpds/processing/timeseries/TimeSeriesConversionService.java
index 2a9f4ffe..e410be40 100644
--- a/processing/src/main/java/edu/harvard/hms/dbmi/avillach/hpds/processing/timeseries/TimeSeriesConversionService.java
+++ b/processing/src/main/java/edu/harvard/hms/dbmi/avillach/hpds/processing/timeseries/TimeSeriesConversionService.java
@@ -9,6 +9,9 @@
 public class TimeSeriesConversionService {
 
     public String toISOString(Long unixTimeStamp) {
+        if (unixTimeStamp == null) {
+            return "Unknown";
+        }
         Instant instant = Instant.ofEpochMilli(unixTimeStamp);
         return DateTimeFormatter.ISO_INSTANT.format(instant);
     }