import java.util.function.BiConsumer; class MyTest<T> { { BiConsumer<Builder<T>, T> builderTBiConsumer = Builder::add; BiConsumer<Builder<T>, T> builderTBiConsumer1 = Builder<T>::add; System.out.println(builderTBiConsumer); System.out.println(builderTBiConsumer1); } public static class Builder<E> { public Builder<E> add(E <warning descr="Parameter 'element' is never used">element</warning>) { return this; } public Builder<E> add(E... <warning descr="Parameter 'elements' is never used">elements</warning>) { return this; } } }