On Thu, 26 Jun 2003, David N. Welton wrote:
> Date: 26 Jun 2003 14:55:02 +0200 > From: David N. Welton <[EMAIL PROTECTED]> > Reply-To: [email protected] > To: [email protected] > Subject: Java + Scripting languages > > > Hi guys, I saw this: > > http://www.jcp.org/en/jsr/detail?id=223 > > The specification may include a Java API that can be used, > possibly through JNI, by an scripting language engine to > access the desired Java objects. > > Can anyone give us a more concrete description of what this is really > about? > The basis for this is exactly what that sentence states -- scripting language users have said they would like to be able to access business logic and data objects inside a servlet-based application from their scripts, in a portable manner. The point of the JSR is to make that sort of thing possible. As Stefano points out, Sam did indeed create some code to do this. Just two little problem though, it's non-thread safe (uses instance variables for per-request state), and it's not scalable. And, it only deals with PHP, but there's lots of other scripting languages (and scripting language users) in the world that could benefit from the same ability. Doing this kind of integration for a scripting language written in Java (or indirectly wrapped by something like BSF) is pretty easy, because the Java code can directly talk to servlet APIs. It's not quite that easy for a scripting language implemented in a non-Java language (like PHP), where you have to create some additional mechanisms to access web application resources from a scripting page. Accessing Java objects defined in the system class loader doesn't require anything new -- JNI provides all the necessary hooks. But, to interact with web app resources, you need to do things like load classes from the webapp's class loader, and gain access to the ServletContext instance, and perhaps even do nice things like utilize the servlet container's session mechanism for scripting languages that don't have such a notion. Such things can be designed and built for a particular server today, but there's no standard approach; hence the JSR. > It looks interesting, because... hey, who wouldn't want to associate > with a million dollar marketing machine:-) It's actually going to be a pretty good win-win ... scripting language users gain access to business logic and services already written in Java, and the Java community has the opportunity to grow by virtue of being useful to people who don't currently use it. > > -- > David N. Welton Craig McClanahan --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
