public static boolean hasAnnotation(Class clazz, String annotationClass) {
        for (Annotation annot : clazz.getDeclaredAnnotations())
            if (annot.annotationType().getName().equals(annotationClass))
                return true;
        return false;
    }
@Test
    public void testHasAnnotationJavassist() throws Exception {
        ClassPool ctPool = ClassPool.getDefault();
        CtClass ctClass = ctPool.getCtClass(AnonymousClassPatchPlugin.class.getName());

        assertTrue(AnnotationHelper.hasAnnotation(ctClass, "org.hotswap.agent.annotation.Plugin"));
        assertFalse(AnnotationHelper.hasAnnotation(ctClass, "xxxx"));
    }