From 49d94866e39c06f72e4d79d51f0a86d2c7c520ce Mon Sep 17 00:00:00 2001
From: Chi Bong Ho <cbho@pih.org>
Date: Fri, 22 Mar 2024 13:13:18 -0400
Subject: [PATCH] null check for queueComingFrom of queueEntry in
 getPreviousQueueEntry

---
 .../openmrs/module/queue/api/impl/QueueEntryServiceImpl.java | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/api/src/main/java/org/openmrs/module/queue/api/impl/QueueEntryServiceImpl.java b/api/src/main/java/org/openmrs/module/queue/api/impl/QueueEntryServiceImpl.java
index 61247f2..e73c1b1 100644
--- a/api/src/main/java/org/openmrs/module/queue/api/impl/QueueEntryServiceImpl.java
+++ b/api/src/main/java/org/openmrs/module/queue/api/impl/QueueEntryServiceImpl.java
@@ -256,15 +256,18 @@ private void endQueueEntry(@NotNull QueueEntry queueEntry) {
 	@Override
 	@Transactional(readOnly = true)
 	public QueueEntry getPreviousQueueEntry(@NotNull QueueEntry queueEntry) {
+		Queue queueComingFrom = queueEntry.getQueueComingFrom();
 		QueueEntrySearchCriteria criteria = new QueueEntrySearchCriteria();
 		criteria.setPatient(queueEntry.getPatient());
 		criteria.setVisit(queueEntry.getVisit());
 		criteria.setEndedOn(queueEntry.getStartedAt());
-		criteria.setQueues(Arrays.asList(queueEntry.getQueueComingFrom()));
+		criteria.setQueues(queueComingFrom == null ? Arrays.asList() : Arrays.asList(queueComingFrom));
 		List<QueueEntry> prevQueueEntries = dao.getQueueEntries(criteria);
 		if (prevQueueEntries.size() == 1) {
 			return prevQueueEntries.get(0);
 		} else if (prevQueueEntries.size() > 1) {
+			// TODO: Exceptions should be translatable and human readable on the frontend.
+			// See: https://openmrs.atlassian.net/browse/O3-2988
 			throw new IllegalStateException("Multiple previous queue entries found");
 		} else {
 			return null;