[FLINK-15706][table-planner-blink] Fix LastValueAggFunctionWithOrderT…

…est compilation error due to incompatible types

This partially reverts the commit dcc1330 and uses the initial approach from apache#10158 of using Enclosed annotation. The problem with the TestSpec approach was that the top level classes shouldn't use generics as they are stripped when instantiated by JUnit runner which may lead to generic signature mismatch.

This closes apache#10915

flink-table/flink-table-planner-blink/src/test/java/org/apache/flink/table/planner/functions/aggfunctions/AggFunctionTestBase.java

@@ -54,29 +54,6 @@
  */
 public abstract class AggFunctionTestBase<T, ACC> {
 
- /**
- * Spec for parameterized aggregate function tests.
- */
- protected static class AggFunctionTestSpec<T, ACC> {
- final AggregateFunction<T, ACC> aggregator;
- final List<List<T>> inputValueSets;
- final List<T> expectedResults;
-
- public AggFunctionTestSpec(
- AggregateFunction<T, ACC> aggregator,
- List<List<T>> inputValueSets,
- List<T> expectedResults) {
- this.aggregator = aggregator;
- this.inputValueSets = inputValueSets;
- this.expectedResults = expectedResults;
- }
-
- @Override
- public String toString() {
- return aggregator.getClass().getSimpleName();
- }
- }
-
  protected abstract List<List<T>> getInputValueSets();
 
  protected abstract List<T> getExpectedResults();

flink-table/flink-table-planner-blink/src/test/java/org/apache/flink/table/planner/functions/aggfunctions/FirstLastValueAggFunctionWithOrderTestBase.java

@@ -36,23 +36,6 @@
  */
 public abstract class FirstLastValueAggFunctionWithOrderTestBase<T> extends AggFunctionTestBase<T, GenericRow> {
 
- /**
- * An AggFunctionTestSpec with input order.
- */
- protected static class AggFunctionWithOrderTestSpec<T> extends AggFunctionTestSpec<T, GenericRow> {
-
- final List<List<Long>> inputOrderSets;
-
- public AggFunctionWithOrderTestSpec(
- AggregateFunction<T, GenericRow> aggregator,
- List<List<Long>> inputOrderSets,
- List<List<T>> inputValueSets,
- List<T> expectedResults) {
- super(aggregator, inputValueSets, expectedResults);
- this.inputOrderSets = inputOrderSets;
- }
- }
-
  protected Method getAccumulateFunc() throws NoSuchMethodException {
  return getAggregator().getClass().getMethod("accumulate", getAccClass(), Object.class, Long.class);
  }