MODHAADM-6 Experiments continued

 - minor tweak

src/main/java/org/folio/harvesteradmin/service/fileimport/InventoryBatchUpdating.java

@@ -1,5 +1,7 @@
 package org.folio.harvesteradmin.service.fileimport;
 
+import io.vertx.core.Future;
+import io.vertx.core.Promise;
 import io.vertx.core.json.JsonArray;
 import io.vertx.core.json.JsonObject;
 import io.vertx.ext.web.RoutingContext;
@@ -14,7 +16,7 @@ public class InventoryBatchUpdating implements RecordReceiver {
     private final JobHandler job;
     private JsonArray inventoryRecordSets = new JsonArray();
 
-    // Blocking queue of one, acting as a turnstile for batches, to upsert them one at a time
+    // Blocking queue of one, acting as a turnstile for batches in order to persist them one at a time
     private final BlockingQueue<BatchOfRecords> turnstile = new ArrayBlockingQueue<>(1);
     private int batchCounter = 0;
     private final InventoryUpdateClient updateClient;
@@ -48,12 +50,13 @@ public void put(String jsonRecord) {
 
     private void releaseBatch(BatchOfRecords batch) {
         try {
-            // stage next batch for upsert, will wait if a previous batch is still in the turnstile
+            // stage next batch for upsert (process will wait if a previous batch is still in the turnstile)
             turnstile.put(batch);
-            persistBatch();
-        } catch (InterruptedException ie) {
-            System.out.println("Error: Queue put operation was interrupted.");
-        }
+            persistBatch().onComplete(na -> {
+                try { turnstile.take(); }
+                catch (InterruptedException e) { throw new RuntimeException(e);}
+            });
+        } catch (InterruptedException ie) { throw new RuntimeException(ie);}
     }
 
     @Override
@@ -66,7 +69,8 @@ public void endOfDocument() {
      * it must be in charge of when to invoke reporting. JobHandler will not
      * otherwise know when the last upsert of a source file of records is done, for example.
      */
-    private void persistBatch() {
+    private Future<Void> persistBatch() {
+        Promise<Void> promise = Promise.promise();
         BatchOfRecords batch = turnstile.peek();
         if (batch != null) {
             if (batch.size() > 0) {
@@ -76,21 +80,16 @@ private void persistBatch() {
                     if (batch.isLastBatchOfFile()) {
                         report(batch);
                     }
-                    try {
-                        // Clear the gate for next batch
-                        turnstile.take();
-                    } catch (InterruptedException ignored) {}
+                    promise.complete();
                 });
             } else { // we get here when the last set of records is exactly 100. We just need to report
                 if (batch.isLastBatchOfFile()) {
                     report(batch);
                 }
-                try {
-                    // Clear the gate for next batch
-                    turnstile.take();
-                } catch (InterruptedException ignored) {}
+                promise.complete();
             }
         }
+        return promise.future();
     }
 
     private void report(BatchOfRecords batch) {