Trampoline in Java 8 with Lambdas and interface defaults

TrampolineLambda.java

public class TrampolineLambda {
    interface TrampolineFunction<T, R> {
        R apply(T...obj);

        public default Object trampoline(T...objs) {
            Object result = apply(objs);
            if (!(result instanceof TrampolineFunction)) {
                return result;
            } else {
                return this;
            }
        }
    }

    // Wrap the call in a TrampolineFunction so that we can avoid StackOverflowError
    static TrampolineFunction<Integer, Object> fibTrampoline = (Integer...objs) -> {
        Integer n = objs[0];
        Integer a = objs.length >= 2 ? objs[1] : 0;
        Integer b = objs.length >= 3 ? objs[2] : 1;

        if (n == 0) return a;
        else return fibTrampoline.trampoline(n-1, b, a+b);
    };

    // Eventually will get a StackOverflowError
    static IntFunction<Integer> regularFib = (int n) -> {
        if (n == 0 || n == 1) return n;
        return regularFib.apply(n - 1) + regularFib.apply(n - 2);
    };

    public static void main(String[] args) {
        // Prints "1556111435"
        System.out.println(fibTrampoline.apply(1000));
    }
}

See also https://github.com/groovy/groovy-core/blob/master/src/main/groovy/lang/TrampolineClosure.java