Mapping call before count()

Reports redundant Stream API calls like map(), or boxed() right before the count() call.

Such calls don't change the final count, so could be removed. It's possible that the code relies on a side effect from the lambda inside such a mapping call. However, relying on side effects inside the stream chain is extremely bad practice. There are no guarantees that the call will not be optimized out in future Java versions.

Example:

  // map() call is redundant
  long count = list.stream().filter(s -> !s.isEmpty()).map(s -> s.trim()).count();

This inspection depends on the Java feature 'Stream and Optional API' which is available since Java 8.

New in 2024.1

Inspection Details
By default bundled with:	IntelliJ IDEA 2024.1, Qodana for JVM 2024.1,
Can be installed with plugin:	Java, 241.16690

Last modified: 29 April 2024