消除lambda中的功能接口的歧义

假设这个:

ExecutorService service = ...;

// somewhere in the code the executorService is used this way:
service.submit(() -> { ... });

lambda表达式默认为Callable.
有没有办法让它实例化Runnable？

谢谢你的帮助.

您可以将其声明为Runnable,或使用强制转换:

Runnable r = () -> { ... };
executorService.submit(r);

要么

executorService.submit((Runnable) () -> { ... });