How to use guava predictions as a filter in the Java 8 stream API

Guava predictions cannot be used as a filter for the Java 8 streaming API

For example, this is not possible:

Number first = numbers.stream()
    .filter( com.google.common.base.Predicates.instanceOf(Double.class)))
    .findFirst()
    .get();

How is it possible to convert a guava predicate to a Java 8 predicate, as follows:

public static <T> Predicate<T> toJava8(com.google.common.base.Predicate<T> guavaPredicate) {
  return (e -> guavaPredicate.apply(e));
}

Number first = numbers.stream()
    .filter( toJava8( instanceOf(Double.class)))
    .findFirst()
    .get();

Question: is there a more elegant way to reuse guava predictions in Java 8?

Solution

The method handle of the apply method of the guava predicate is a functional interface that can be used as a filter:

Number first = numbers.stream()
    .filter(Predicates.instanceOf(Double.class)::apply)
    .findFirst()
    .get();