Exception in thread "main" org.apache.flink.table.api.ValidationException: Could not resolve over call.

[大森林]

I'm learning Official document-Over Window Aggregation

My pojo is:

https://paste.ubuntu.com/p/kPydGd2Cwd/

Completed test code is:

https://paste.ubuntu.com/p/KyCVxBz254/

The error I got is:

Exception in thread "main" org.apache.flink.table.api.ValidationException: Could not resolve over call.

at org.apache.flink.table.expressions.resolver.rules.OverWindowResolverRule$ExpressionResolverVisitor.lambda$visit$0(OverWindowResolverRule.java:72)

at java.util.Optional.orElseThrow(Optional.java:290)

at org.apache.flink.table.expressions.resolver.rules.OverWindowResolverRule$ExpressionResolverVisitor.visit(OverWindowResolverRule.java:72)

at org.apache.flink.table.expressions.resolver.rules.OverWindowResolverRule$ExpressionResolverVisitor.visit(OverWindowResolverRule.java:58)

at org.apache.flink.table.expressions.ApiExpressionVisitor.visit(ApiExpressionVisitor.java:39)

at org.apache.flink.table.expressions.UnresolvedCallExpression.accept(UnresolvedCallExpression.java:132)

at org.apache.flink.table.expressions.resolver.rules.OverWindowResolverRule.lambda$apply$0(OverWindowResolverRule.java:54)

at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)

at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1374)

at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)

at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)

at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)

at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)

at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)

at org.apache.flink.table.expressions.resolver.rules.OverWindowResolverRule.apply(OverWindowResolverRule.java:55)

at org.apache.flink.table.expressions.resolver.ExpressionResolver.lambda$null$1(ExpressionResolver.java:211)

at java.util.function.Function.lambda$andThen$1(Function.java:88)

at java.util.function.Function.lambda$andThen$1(Function.java:88)

at java.util.function.Function.lambda$andThen$1(Function.java:88)

at java.util.function.Function.lambda$andThen$1(Function.java:88)

at org.apache.flink.table.expressions.resolver.ExpressionResolver.resolve(ExpressionResolver.java:178)

at org.apache.flink.table.operations.utils.OperationTreeBuilder.projectInternal(OperationTreeBuilder.java:191)

at org.apache.flink.table.operations.utils.OperationTreeBuilder.project(OperationTreeBuilder.java:170)

at org.apache.flink.table.api.internal.TableImpl$OverWindowedTableImpl.select(TableImpl.java:963)

at OverWindowAggregation.main(OverWindowAggregation.java:39)

Could you tell me where I am wrong in my code?

Thanks for your help.