(in-ns 'clojure.test-clojure.annotations)

(import [java.lang.annotation Annotation Retention RetentionPolicy Target ElementType])

(definterface Foo (foo []))

(deftype #^{Deprecated true

Retention RetentionPolicy/RUNTIME}

Bar [#^int a

#^{:tag int

Deprecated true

Retention RetentionPolicy/RUNTIME} b]

Foo (#^{Deprecated true

Retention RetentionPolicy/RUNTIME}

foo [this] 42))

(defn annotation->map

"Converts a Java annotation (which conceals data)

[#^java.lang.annotation.Annotation o]

(cond

(instance? Annotation o)

(let [type (.annotationType o)

itfs (-> (into #{type} (supers type)) (disj java.lang.annotation.Annotation))

data-methods (into #{} (mapcat #(.getDeclaredMethods %) itfs))]

(into

{:annotationType (.annotationType o)}

(map

(fn [m] [(keyword (.getName m)) (annotation->map (.invoke m o nil))])

data-methods)))

(or (sequential? o) (.isArray (class o)))

(map annotation->map o)

:else o))

(def expected-annotations

#{{:annotationType java.lang.annotation.Retention, :value RetentionPolicy/RUNTIME}

{:annotationType java.lang.Deprecated}})

(deftest test-annotations-on-type

(is (=

expected-annotations

(into #{} (map annotation->map (.getAnnotations Bar))))))

(deftest test-annotations-on-field

(is (=

expected-annotations

(into #{} (map annotation->map (.getAnnotations (.getField Bar "b")))))))

(deftest test-annotations-on-method

(is (=

expected-annotations

(into #{} (map annotation->map (.getAnnotations (.getMethod Bar "foo" nil)))))))