refactor: make ReconcileResult immutable

Author: metacosm

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/reconciler/dependent/ReconcileResult.java

@@ -8,9 +8,7 @@
 
 public class ReconcileResult<R> {
 
-  private Map<R, Operation> resourceOperations = new HashMap<>(1);
-
-  public ReconcileResult() {}
+  private final Map<R, Operation> resourceOperations;
 
   public static <T> ReconcileResult<T> resourceCreated(T resource) {
     return new ReconcileResult<>(resource, Operation.CREATED);
@@ -24,6 +22,21 @@ public static <T> ReconcileResult<T> noOperation(T resource) {
     return new ReconcileResult<>(resource, Operation.NONE);
   }
 
+  @SafeVarargs
+  public static <T> ReconcileResult<T> aggregatedResult(ReconcileResult<T>... results) {
+    if (results == null) {
+      throw new IllegalArgumentException("Should provide results to aggregate");
+    }
+    if (results.length == 1) {
+      return results[0];
+    }
+    final Map<T, Operation> operations = new HashMap<>(results.length);
+    for (ReconcileResult<T> res : results) {
+      res.getSingleResource().ifPresent(r -> operations.put(r, res.getSingleOperation()));
+    }
+    return new ReconcileResult<>(operations);
+  }
+
   @Override
   public String toString() {
     return resourceOperations.entrySet().stream().collect(Collectors.toMap(
@@ -33,7 +46,11 @@ public String toString() {
   }
 
   private ReconcileResult(R resource, Operation operation) {
-    resourceOperations.put(resource, operation);
+    resourceOperations = Map.of(resource, operation);
+  }
+
+  private ReconcileResult(Map<R, Operation> operations) {
+    resourceOperations = Collections.unmodifiableMap(operations);
   }
 
   public Optional<R> getSingleResource() {
@@ -45,17 +62,11 @@ public Operation getSingleOperation() {
         .orElseThrow();
   }
 
+  @SuppressWarnings("unused")
   public Map<R, Operation> getResourceOperations() {
     return resourceOperations;
   }
 
-  public void addReconcileResult(ReconcileResult<R> result) {
-    result.getSingleResource().ifPresent(r -> {
-      resourceOperations.put(r, result.getSingleOperation());
-    });
-
-  }
-
   public enum Operation {
     CREATED, UPDATED, NONE
   }

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/AbstractDependentResource.java

@@ -40,17 +40,19 @@ public AbstractDependentResource() {
 
   @Override
   public ReconcileResult<R> reconcile(P primary, Context<P> context) {
-    var count = bulk ? bulkDependentResource.count(primary, context) : 1;
     if (bulk) {
+      final var count = bulkDependentResource.count(primary, context);
       deleteBulkResourcesIfRequired(count, lastKnownBulkSize(), primary, context);
       adjustDiscriminators(count);
+      @SuppressWarnings("unchecked")
+      final ReconcileResult<R>[] results = new ReconcileResult[count];
+      for (int i = 0; i < count; i++) {
+        results[i] = reconcileIndexAware(primary, i, context);
+      }
+      return ReconcileResult.aggregatedResult(results);
+    } else {
+      return reconcileIndexAware(primary, 0, context);
     }
-    ReconcileResult<R> result = new ReconcileResult<>();
-    for (int i = 0; i < count; i++) {
-      var res = reconcileIndexAware(primary, i, context);
-      result.addReconcileResult(res);
-    }
-    return result;
   }
 
   protected void deleteBulkResourcesIfRequired(int targetCount, int actualCount, P primary,