chore(PR): implement PR comments

Author: HeleneW-dot

data-migrator/core/src/main/java/io/camunda/migration/data/impl/clients/C7Client.java

@@ -17,6 +17,7 @@
 import static io.camunda.migration.data.impl.logging.C7ClientLogs.FAILED_TO_FETCH_TENANTS;
 import static io.camunda.migration.data.impl.util.ExceptionUtils.callApi;
 import static java.lang.String.format;
+import static java.util.stream.Collectors.toList;
 import static org.camunda.bpm.engine.ActivityTypes.CALL_ACTIVITY;
 
 import io.camunda.migration.data.config.property.MigratorProperties;
@@ -162,21 +163,20 @@ public HistoricActivityInstance getHistoricActivityInstance(String c7Id) {
    * Finds the activity that started a child process instance.
    */
   public HistoricActivityInstance findCallActivityByCalledProcessInstanceId(String parentProcessInstanceId,
-                                                                            String childProcessInstanceId) {
+                                                                                  String childProcessInstanceId) {
     var query = historyService.createHistoricActivityInstanceQuery()
         .processInstanceId(parentProcessInstanceId)
         .activityType(CALL_ACTIVITY)
         .orderByHistoricActivityInstanceStartTime()
         .asc()
         .orderByHistoricActivityInstanceId()
         .asc();
-
-    return callApi(() -> Objects.requireNonNull(query.list()
-            .stream()
-            .filter(activity -> childProcessInstanceId.equals(activity.getCalledProcessInstanceId()))
-            .findFirst()
-            .orElse(null)),
+    List<HistoricActivityInstance> result = callApi(query::list,
         format(FAILED_TO_FETCH_HISTORIC_ELEMENT, "Parent activity for child process instance", childProcessInstanceId));
+    return result.stream()
+        .filter(activity -> childProcessInstanceId.equals(activity.getCalledProcessInstanceId()))
+        .findFirst()
+        .orElse(null);
   }
 
   /**
@@ -318,7 +318,7 @@ public void fetchAndHandleHistoricRootProcessInstances(Consumer<IdKeyDbModel> ca
         .page(offset -> query.listPage(offset, properties.getPageSize())
             .stream()
             .map(hpi -> new IdKeyDbModel(hpi.getId(), hpi.getStartTime()))
-            .collect(Collectors.toList()))
+            .collect(toList()))
         .callback(callback);
   }
 
@@ -555,7 +555,7 @@ public List<HistoricDecisionInstance> findChildDecisionInstances(String rootDeci
 
     return query.list().stream()
         .filter(decisionInstance -> decisionInstance.getRootDecisionInstanceId() != null)
-        .collect(Collectors.toList());
+        .collect(toList());
   }
 
 }

data-migrator/core/src/main/java/io/camunda/migration/data/impl/history/ProcessInstanceMigrator.java

@@ -176,6 +176,7 @@ protected void resolveParentAndRootKeys(
    *
    * @param builder the process instance builder
    * @param c7ProcessInstanceId the historic process instance ID from Camunda 7
+   * @param c7SuperProcessInstanceId the historic parent process instance ID from Camunda 7
    */
   protected void resolveParentFlowNodeInstanceKey(
       ProcessInstanceDbModel.ProcessInstanceDbModelBuilder builder,
@@ -187,7 +188,7 @@ protected void resolveParentFlowNodeInstanceKey(
     if (callActivity != null && isMigrated(callActivity.getId(), HISTORY_FLOW_NODE)) {
       Long parentFlowNodeInstanceKey = dbClient.findC8KeyByC7IdAndType(callActivity.getId(), HISTORY_FLOW_NODE);
       if (parentFlowNodeInstanceKey != null) {
-         builder.parentElementInstanceKey(parentFlowNodeInstanceKey);
+        builder.parentElementInstanceKey(parentFlowNodeInstanceKey);
       }
     }
   }