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Play framework for Java - a radical rethink of Java web app development?

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Re: Play framework for Java - a radical rethink of Java web app development?

#51

Post by simonw »

kls wrote: post #17

"The Play framework makes it easier to build Web applications with Java" Maybe you should not be building web applications with Java or C# or . Maybe you should be building web services with these languages and using AJAX, a client side toolkit, Javscript, HTML and CSS to build a UI that communicates with said services. Maybe this decouples your UI implementation from your business logic implementation so you can go…

The Web I fell in love with is the Web of URLs that respond to a GET request with a page full of HTML.

Re: Play framework for Java - a radical rethink of Java web app development?

#52

Post by ilyak »

bad_user wrote: post #34
kls wrote: post #26

Earlier quoted context omitted.

Neither is an IPhone app, but I can guarantee you that most of the logic I use for my "Web Application" will be reused by my IPhone application. With the exception of my templating, work-flow and UI specific logic, so it begs the question why am I implementing my templating, workflow UI specific logic, in my "Web Application" (it's not reusable). Unless it really is a web UI to my enterprise application in which my U…

Because this is a premature optimization. I've seen companies falling at the other extreme ... making the interface "totally" decoupled, so that they could replace the UI anytime they wanted. That's why monstrosities like XSLT appeared. But I haven't seen any example of a good application yet that does this successfully, because whether you like it or not, the web UI will require backend logic that your iPhone app do…

XSLT makes for a nice templating engine.

Re: Play framework for Java - a radical rethink of Java web app development?

#53

Post by ilyak »

mcav wrote: post #43
modoc wrote: post #29

Earlier quoted context omitted.

I haven't done any real dev with those frameworks you list so I'm wondering how do you manage session state? user profile, shopping cart, breadcrumbs, multi-request flows, etc... Do you write/read all that into the db/memcached for each request?

Yes. PHP does the same thing. Actually, most frameworks do that; very few keep state within the application server between requests. Statelessness, in that respect, improves scalability.

...while reducing perfomance...

Re: Play framework for Java - a radical rethink of Java web app development?

#54

Post by kls »

simonw wrote: post #51
kls wrote: post #17

"The Play framework makes it easier to build Web applications with Java" Maybe you should not be building web applications with Java or C# or . Maybe you should be building web services with these languages and using AJAX, a client side toolkit, Javscript, HTML and CSS to build a UI that communicates with said services. Maybe this decouples your UI implementation from your business logic implementation so you can go…

The Web I fell in love with is the Web of URLs that respond to a GET request with a page full of HTML.

I liked it when we figured our how to POST to a C application and then Perl came along and ruined the party. I had to learn a new language just to keep doing CGI. After that, no one but yahoo would hire a CGI C developer.

Re: Play framework for Java - a radical rethink of Java web app development?

#55

Post by modoc »

kls wrote: post #44
modoc wrote: post #35

Earlier quoted context omitted.

Building/maintaining that sounds way more complex than writing a JSP. In my experience, if you architect your server-side components well, if/when you want to expose something as a web service you can prop up a web service that's basically just a thin wrapper around the relevant backend component(s). It avoids the "premature optimization" of building everything as a bunch of micro and aggregate services that you may…

If you are a one man show maybe, but if you are a team it is far more maintainable because each concern is clearly delineated. JSP is not easier for a HTML designer nor is ASP or PHP it is an amalgamation of languages composites into a document. It is only easier for a code developer and that it the crux. Usually a company starts out as a one man shop with a code developer and then graduates to a team. Having to teac…

I typically work with largish teams on very large websites (cingular.com, jcrew.com, ulta.com, pcavote.com, etc...).

With good frameworks most JSPs are very close to normal HTML and we actually usually have: designers/UX folks who provide PS docs/images/etc..., front end devs (JSP/JS/AJAX impl folks) who take those and make real working JSP pages out of them, and back-end devs who write the Java backing components.

You seem to be expecting these new developers who are just learning HTML to know how to build complex pages using aggregate web service calls via JS, based on a non-standard in-house system.

Even if you don't have separate designers and front-end devs, and I've worked at several places like that, helping HTML designers figure out JSP using a good framework (ATG, JSF) really isn't that bad, it's just a few new tags which are really well documented all over the web.

While I am a Java dev/arch, my "view point" is typically that of a lead architect, team lead, or project lead, so making sure people can get stuff done, regardless of what role they're in is key.

Do you have any live examples of websites built using your proposed method?

Re: Play framework for Java - a radical rethink of Java web app development?

#56

Post by modoc »

mcav wrote: post #43
modoc wrote: post #29

Earlier quoted context omitted.

I haven't done any real dev with those frameworks you list so I'm wondering how do you manage session state? user profile, shopping cart, breadcrumbs, multi-request flows, etc... Do you write/read all that into the db/memcached for each request?

Yes. PHP does the same thing. Actually, most frameworks do that; very few keep state within the application server between requests. Statelessness, in that respect, improves scalability.

PHP has session variables to put state objects into which are persisted between requests. Right?

Re: Play framework for Java - a radical rethink of Java web app development?

#57

Post by kls »

modoc wrote: post #35
kls wrote: post #30

Earlier quoted context omitted.

No one said that they have to be micro services. One should provide composite services that provide all of the data for a work-flow. Then use a pub-sub event based model to notify the UI of available data. This way components stay loosely coupled and are only listening for an event that injects the relevant data that they need. This results in a single call to a composite service yet the micro services are available…

Building/maintaining that sounds way more complex than writing a JSP. In my experience, if you architect your server-side components well, if/when you want to expose something as a web service you can prop up a web service that's basically just a thin wrapper around the relevant backend component(s). It avoids the "premature optimization" of building everything as a bunch of micro and aggregate services that you may…

"building everything as a bunch of micro and aggregate services that you may or may not actually make use of in the future"

I wanted to touch on this real quick, The point of letting the client deal with it's concern, is that you can prototype and user acceptance test you application before you ever write a service. Then you only have to build what you need to support your UI and what ever batch processing you need. It is a far more agile process. Not only do you have a working UI but you have a service inventory of functionality that need to be implemented to support you UI. From there you can build out your service tier and if you so chose look at the next likely UI and do some due diligence to see if you are going to need more micro services to support you next endeavor. You may not chose to build them but you can at least architect the solution with the next endeavor in mind.

Re: Play framework for Java - a radical rethink of Java web app development?

#58

Post by guillaume »

scotth wrote: post #49

How does the following work? Must be a preprocessing step, if I'm not mistaken. With play, you can just write: Article article = Article.findById(id); User user = User.getConnected(); render(article, user); And retrieve objects from their Java local name in the template. That saves a lot of useless lines of code...

Yep there is one step of byte code enhancement, during the compilation phase. But as the compilation phase itself it totally transparent, you can't call that a 'preprocessing step'.

Re: Play framework for Java - a radical rethink of Java web app development?

#59

Post by guillaume »

mhd wrote: post #42

Hmm, too much code in the template library, too much magic in general. I do like the general packacking, the automatic compilation and the snazzy error and testing interfaces. Seems a bit hard to change from their Groovy template system to something like StringTemplate, though.

Although I think that the built-in template system is very very nice, it would be really easy to write a play module that provide any template engine you want.

Re: Play framework for Java - a radical rethink of Java web app development?

#60

Post by hariharan »

Nice collection of web tools. Especially ready made libraries for validation, captcha etc and a built-in template engine.

But I am not convinced with 'on the fly' compilation because most editors already do a better job there and refreshing the web page to look for compilation errors does not look productive.

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