guava/src/com/google/common/reflect/Invokable.java
public final <R1 extends R> Invokable<T, R1> returning(Class<R1> returnType) {
    return returning(TypeToken.of(returnType));
  }
public final <R1 extends R> Invokable<T, R1> returning(Class<R1> returnType) {
    return returning(TypeToken.of(returnType));
  }
Explicitly specifies the return type of this {@code Invokable}. For example:

<pre>{@code
Method factoryMethod = Person.class.getMethod("create");
Invokable<?, Person> factory = Invokable.of(getNameMethod).returning(Person.class);
}</pre>