fix the test and checkstyle

Author: 1996fanrui

flink-autoscaler/src/main/java/org/apache/flink/autoscaler/DelayedScaleDown.java

@@ -38,6 +38,7 @@
 /** All delayed scale down requests. */
 public class DelayedScaleDown {
 
+    /** Details of the recommended parallelism. */
     @Data
     public static class RecommendedParallelism {
         @Nonnull private final Instant triggerTime;
@@ -132,12 +133,6 @@ public DelayedScaleDown() {
         this.delayedVertices = new HashMap<>();
     }
 
-    // TODO : remove this and refactor tests;
-    public VertexDelayedScaleDownInfo triggerScaleDown(
-            JobVertexID vertex, Instant triggerTime, int parallelism) {
-        return triggerScaleDown(vertex, triggerTime, parallelism, false);
-    }
-
     /** Trigger a scale down, and return the corresponding {@link VertexDelayedScaleDownInfo}. */
     @Nonnull
     public VertexDelayedScaleDownInfo triggerScaleDown(

flink-autoscaler/src/test/java/org/apache/flink/autoscaler/DelayedScaleDownTest.java

@@ -131,19 +131,19 @@ void testMaxRecommendedParallelismForSlidingWindow() {
                 instant);
         // 5, [8, 6, 4, 3] -> 8
         assertVertexDelayedScaleDownInfo(
-                delayedScaleDown.triggerScaleDown(vertex, instant.plusSeconds(4), 3),
+                delayedScaleDown.triggerScaleDown(vertex, instant.plusSeconds(4), 3, true),
                 instant,
                 new DelayedScaleDown.RecommendedParallelism(instant.plusSeconds(1), 8, false),
                 instant.plusSeconds(1));
         // 5, 8, [6, 4, 3, 3] -> 6
         assertVertexDelayedScaleDownInfo(
-                delayedScaleDown.triggerScaleDown(vertex, instant.plusSeconds(5), 3),
+                delayedScaleDown.triggerScaleDown(vertex, instant.plusSeconds(5), 3, true),
                 instant,
                 new DelayedScaleDown.RecommendedParallelism(instant.plusSeconds(2), 6, true),
                 instant.plusSeconds(2));
         // 5, 8, 6, [4, 3, 3, 3] -> 4
         assertVertexDelayedScaleDownInfo(
-                delayedScaleDown.triggerScaleDown(vertex, instant.plusSeconds(6), 3),
+                delayedScaleDown.triggerScaleDown(vertex, instant.plusSeconds(6), 3, true),
                 instant,
                 new DelayedScaleDown.RecommendedParallelism(instant.plusSeconds(3), 4, true),
                 instant.plusSeconds(3));

flink-autoscaler/src/test/java/org/apache/flink/autoscaler/state/AbstractAutoScalerStateStoreTest.java

@@ -207,8 +207,9 @@ protected void testDiscardAllState() throws Exception {
         stateStore.storeScalingTracking(ctx, scalingTracking);
 
         var delayedScaleDown = new DelayedScaleDown();
-        delayedScaleDown.triggerScaleDown(new JobVertexID(), Instant.now(), 10);
-        delayedScaleDown.triggerScaleDown(new JobVertexID(), Instant.now().plusSeconds(10), 12);
+        delayedScaleDown.triggerScaleDown(new JobVertexID(), Instant.now(), 10, true);
+        delayedScaleDown.triggerScaleDown(
+                new JobVertexID(), Instant.now().plusSeconds(10), 12, true);
 
         stateStore.storeDelayedScaleDown(ctx, delayedScaleDown);