Sorry you still miss my point. I will try to explain myself better 
First forget the word Syntax, as i have written before the syntax does not matter at all.
Let me try it again with one example.
this
component implementsJava="Whatever" {} // Syntax A
...
component implements="java:Whatever" {} // Syntax B
...
component java={implements:"Whatever"} {} // Syntax C
defines that this component needs to implement the Java Interface “Whatever”, this is checked at the same time a regular “implements” is checked. the only difference to a component interface is how the interface itself is read, otherwise it is exactly the same.
On the other side this
// Syntax A
@java(interface:"Whatever")
component {}
// Syntax B
/**
* @java {interface:"Whatever"}
*/
component {}
// Syntax C
/**
* @interface Whatever
*/
component {}
Is something completely different, Lucee does not care about this at all when loading a component, this “annotation” only come into play when you try to convert that component to a certain java class, for example by passing to a Java method that looks like this
void test(Whatever w);
or you do
javaCast("Whatever",cfc);
So you can use that component as a regular component and the annotation only comes into action, when you use that component in a specific way.
So what is the difference between the existing “doc tags/undefined attributes set” and my suggested annotations?
doc tags never influence the flow of the language itself unless you read them and act based on your own logic.
Doc tags are completely stupid and have now logic on their own. Instead of using doc tags you could also use a file name pattern and achieve the same goal
So instead of
component bean=true {
}
you could also do
AddressBean.cfc
and based on the File name make certain actions.
How COULD annotations work?
Let me try to make an other example (please have in mind that this is just an idea how annotations could work in Lucee i just made up now)
Let’s go back to this example
component bean=true {
}
as i said, Lucee does not care at all about that attribute at any time, with annotation i can make Lucee care.
You could for example do something like this in the Application.cfc/Server.cfc/Web.cfc
this.annotations.bean={
type:"component"
retention:"instantiation"
action:function(attrValue,???){???} // could also be a Java Lambda
}
then the function defined under “action” get called when the component is instantiated and can influence that process.
Let say we only teach Lucee annotations but nothing else, so Lucee has no clue what the following is and does not care (simply metadata)
component java={implements:"Whatever"} {
}
You could add this to the Application.cfc
this.annotations.java={
type:"component"
retention:"casting"
action:function(attr,cfc){???;return createDynamicProxy(cfc,attr.implements)}
}
In that case we wrap the component with a proxy class when passed to a Java method
this would give you far more influence into the language as you have today, as i have written before and this has nothing to do with adding a new syntax for something that already exists.
Actually we do not necessary to have do add a new syntax at all. It’s all about the possibility to inject your code into specific actions Lucee does.
My goal is not to blindly adapt something from Java, the hole “define a Java interface for a component/convert a UDF to Java Lambda” made me thinking about how in CFML this is handled in general today.
How do we tell a component that it also can be used as a webservice endpoint (Rest and Soap) , a Hibernate mapping or how we convert a component to a json string. Is CFML/Lucee consistent on that and what would be the logical approach to add support for a java interface or Java Lambda mapping?
This raised the question for me, “could annotation” be an approach for all of this?
It is all about the greater picture.
sidenote:
It is confusing today in CFML that you can define metadata via tag attributes and doc tags, that would raise the question with for example this
component rest=true restpath="/susi" {}
for me that is a backed in annotation the more logical syntax would be
@rest true
@restpath "/susi"
component rest=true {}
or if you prefer
/**
* @rest true
* @restpath "/susi"
*/
component rest=true {}
(syntax does not matter)
But of course we cannot change that.
Hope this makes now a little bit more sense.
I always think language discussions should start with the existing mechanisms and ask why those can’t be used.