Compiling a servlet independently of a container - source of 'official' servlet-api?
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I've come back to building web applications after a couple of years and realised I've never once compiled a servlet without depending on whatever container I happen to be using.

I can of course carry on doing that, but I'd still prefer some kind of 'official' servlet api JAR.

I found one here: http://repo.maven.apache.org/maven2/javax/servlet/servlet-api/2.5/

But what I don't understand is how that got there? It's odd that it's not a group id starting with com.sun or com.oracle? 

The only other official method I can think of is depending on the Glassfish implementation?

Thanks