AnnotationによるEnumのFieldのデフォルト引数実装

Test.java

@Target(ElementType.FIELD)
@Retention(RetentionPolicy.RUNTIME)
@interface Default{
	String value() default "test";
}


enum Test{
	@Default FOO,BAR;
	String value;
	
	Test(){
		Function<String, Optional<Field>> fieldGetter=createFieldGetter(this.getClass());
		fieldGetter.apply(this.toString())
		.flatMap(enun->Optional.ofNullable(enun.getAnnotation(Default.class)))
		.ifPresent(annotation->{
			Arrays.stream(annotation.annotationType().getDeclaredMethods())
			.forEach(method->{
				fieldGetter.apply(method.getName())
				.filter(field->field.getType().isAssignableFrom(method.getReturnType()))
				.ifPresent(field->{
					try {
						field.set(this, method.invoke(annotation));
					} catch (IllegalAccessException|InvocationTargetException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
				});
			});
		});
		System.out.println(this.value);
	}
	// ラムダ内で発生した例外を握りつぶせなかったのでボツ
	<T> Optional<T> getValue(Supplier<T> f, Class<? extends Exception>... exceptions ) {
		try{
			return Optional.ofNullable(f.get());
		}catch(Exception e){
			return Optional.empty();
		}
	}
	
	Function<String, Optional<Field>> createFieldGetter(Class<?> clazz){
		return (name) -> Hoge.getField(clazz, name);
	}
	Optional<Field> getField(Class<?> clazz,String name){
		try {
			return Optional.ofNullable(clazz.getDeclaredField(name));
		} catch (NoSuchFieldException | SecurityException e) {
			//全てを握りつぶすマン！！
		}
		return Optional.empty();
	}
	
}