org.apache.flink.api.common.functions.InvalidTypesException

最新推荐文章于 2025-07-17 00:11:50 发布

优优我心

最新推荐文章于 2025-07-17 00:11:50 发布

阅读量3.6k

点赞数 3

CC 4.0 BY-SA版权

文章标签： flink lambda

本文链接：https://blog.youkuaiyun.com/weixin_41608066/article/details/88821578

本文探讨了在使用Flink时遇到的`org.apache.flink.api.common.functions.InvalidTypesException`问题，该问题源于lambda表达式的类型信息在某些编译器下无法被正确提取。Flink依赖于类型继承来获取信息，但lambda的匿名特性导致困难。解决方案是根据官方文档，当使用如flatmap等算子时，需要手动指定返回类型，例如通过调用`Types`进行类型声明。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

org.apache.flink.api.common.functions.InvalidTypesException: The return type of function 'main(Main1.java:15)' could not be determined automatically, due to type erasure. You can give type information hints by using the returns(...) method on the result of the transformation call, or by letting your function implement the 'ResultTypeQueryable' interface.
	at org.apache.flink.streaming.api.transformations.StreamTransformation.getOutputType(StreamTransformation.java:386)
	at org.apache.flink.streaming.api.datastream.DataStream.getType(DataStream.java:175)
	at org.apache.flink.streaming.api.datastream.DataStream.filter(DataStream.java:672)
	at main.Main1.main(Main1.java:19)
Caused by: org.apache.flink.api.common.functions.InvalidTypesException: The generic type parameters of 'Collector' are missing. 
It seems that your compiler has not stored them into the .class file. 
Currently, only the Eclipse JDT compiler preserves the type information necessary to use the lambdas feature