Fix PatientIdPartitionInterceptor where patient ID has hashCode equal to Integer.MIN_VALUE. (#3275)

* Fix PatientIdPartitionInterceptor for case where patient ID has hashCode equal to Integer.MIN_VALUE

* Fix PatientIdPartitionInterceptor for case where patient ID has hashCode equal to Integer.MIN_VALUE

Co-authored-by: ianmarshall <ian@simpatico.ai>

hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/5_7_0/3275-fix-patient-id-partition-interceptor-issue.yaml

@@ -0,0 +1,5 @@
+---
+type: fix
+issue: 3275
+title: "In rare cases where patient ID String happened to have hashCode equal to Integer.MIN_VALUE,
+   PatientIdPartitionInterceptor would generate an invalid partition ID. This has been fixed."

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/interceptor/PatientIdPartitionInterceptor.java

@@ -236,7 +236,7 @@ public class PatientIdPartitionInterceptor {
 	 */
 	@SuppressWarnings("unused")
 	protected int providePartitionIdForPatientId(RequestDetails theRequestDetails, String theResourceIdPart) {
-		return Math.abs(theResourceIdPart.hashCode()) % 15000;
+		return Math.abs(theResourceIdPart.hashCode() % 15000);
 	}
 
 	/**

hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/interceptor/PatientIdPartitionInterceptorTest.java

@@ -91,6 +91,23 @@ public class PatientIdPartitionInterceptorTest extends BaseJpaR4SystemTest {
 		});
 	}
 
+	/**
+	 * This is an edge case where a client assigned ID has a Java hashCode equal to Integer.MIN_VALUE.
+	 */
+	@Test
+	public void testCreatePatient_polygenelubricants() {
+		Patient patient = new Patient();
+		patient.setId("Patient/polygenelubricants");
+		patient.setActive(true);
+		DaoMethodOutcome update = myPatientDao.update(patient);
+
+		runInTransaction(() -> {
+			ResourceTable pt = myResourceTableDao.findAll().iterator().next();
+			assertEquals("polygenelubricants", pt.getIdDt().getIdPart());
+			assertEquals(8648, pt.getPartitionId().getPartitionId());
+		});
+	}
+
 	@Test
 	public void testCreatePatient_NonClientAssignedId() {
 		Patient patient = new Patient();