Intellij IDEA cannot enable the "andThen" function interface method when referencing the :: andThen function

Question

How can I get IntellijIDEA to find the 'andThen' method of the main java 8 'Function' interface when using the Funciton :: andThen notation? I have tried many things unsuccessfully.

My intellijIDEA module is configured for java 8, used by sdk - this is oracle java 8, I invalidated caches and tried several other things, but still the editor notes, and then as: "the method cannot be resolved" and "then", ".

I can run and build this sample, so I think it has something to do with a static code analyzer. Maybe a mistake?

package foo.bar;

import java.util.ArrayList;
import java.util.List;
import java.util.function.Function;

public class Meh {


    public static void main(String... args) {


        final List<Function<String, String>> fs = new ArrayList<>();
        fs.add(s -> s + "1");
        fs.add(s -> s + "2");

        final Function<String, String> f =
                fs.stream()
                        //copmiles from cli and project->make, but editor shows: Cannot resolve method 'andThen'
                        .reduce(Function::andThen)
                        .get();

        System.out.println(f.apply(""));//succesfully prints 12

        final Function<String,String> f2 = f.andThen(s-> s+"a");

        //succesfully prints 12a
        System.out.println(f2.apply(""));


    }

}

- , f.andThen, . , :: andThen.

eclipse. , , → make

Answer 1

, -, IntelliJ 15.0.2, 15.0.1 .

, , " Java.Error", :

• IDEA-146604 () (Enum:: compareTo)
• IDEA-147873 () , lambdas/method