jet.Annotation

Create a supertype for all Kotlin annotations, jet.Annotation.
Map java.lang.annotation.Annotation to jet.Annotation and vice versa.
Add extension function "annotationType()" to every annotation, similar to java.lang.annotation.Annotation.annotationType()
 #KT-1620 Fixed

libraries/stdlib/src/kotlin/Annotations.kt

@@ -0,0 +1,9 @@
+package kotlin
+
+import java.lang.reflect.Proxy
+
+public fun <T : Annotation> T.annotationType() : Class<out T> {
+    val invocationHandler = Proxy.getInvocationHandler(this)!!
+    val method = this.javaClass.getMethod("annotationType")
+    return invocationHandler.invoke(this, method, array<Object>())!! as Class<out T>
+}

libraries/stdlib/test/AnnotationsTest.kt

@@ -0,0 +1,36 @@
+package test.annotations
+
+import kotlin.*
+import kotlin.test.assertTrue
+import org.junit.Test as test
+import java.lang.annotation.*
+
+
+Retention(RetentionPolicy.RUNTIME)
+annotation class MyAnno
+
+MyAnno
+Deprecated
+class AnnotatedClass
+
+
+class AnnotationTest {
+    test fun annotationType() {
+        val annotations = javaClass<AnnotatedClass>().getAnnotations()!!
+        
+        var foundMyAnno = false
+        var foundDeprecated = false
+        
+        for (annotation in annotations) {
+            val clazz = annotation!!.annotationType()
+            when {
+                clazz == javaClass<MyAnno>() -> foundMyAnno = true
+                clazz == javaClass<Deprecated>() -> foundDeprecated = true
+                else -> {}
+            }
+        }
+        
+        assertTrue(foundMyAnno)
+        assertTrue(foundDeprecated)
+    }
+}