annotations - Annotate Type Parameter in Java for Kotlin Compiler -

in java, have following method:

public optional<foo> getfoo() {     // return non-null value } 

in kotlin code, return type of method given optional<foo!>!. using @nonnull annotation can cut down optional<foo!> (i.e. foo type not null-checked anymore).

is there way annotate method make kotlin compiler null-check return value correctly?

you can annotating type use of foo of nullability annotations kotlin compiler understands. unfortunately, annotation libraries list don't support type use annotation.

i found @notnull org.jetbrains:annotations:15.0 (but not 13.0) has type_use target, can add library dependency project , annotate type use:

import org.jetbrains.annotations.notnull;  ...  public @notnull optional<@notnull foo> getfoo() {     // return non-null value } 

then return type seen optional<foo> in kotlin.

this, of course, can done other nullability annotations list mentioned above support type_use target.