What are the different way a bean can be created in web development? I know we can use <jsp:useBean />, <bean:define />, or JSON format. Are there more choices? What are their advantages or disadvantages?
I know that this may sound harsh, but if you are creating beans in a jsp page, you're doing it wrong. jsp:useBean and friends are holdovers from the bad old days.
If you aren't already, you should be using a sever-side MVC framework - Spring is good, Struts will work. The 'controller' or 'action' of your framework should then expose the required beans to the jsp page. The jsp page can then access them via jstl.
By no means should you be writing any Java code in a jsp, and that includes invoking methods of a bean defined with jsp:useBean.
Also, JSON creates javascrript objects, not java objects.
This is a fundamental and very important difference. If you don't understand the difference, I urge you to go back and read a bit more until you do understand the difference.
Related
I need some assistance in creating a simple html page and locate it in the server.
Since I couldnt find it in the doc I tried to put a index2.html file in the /public library and when I tried to get receive it using
http://127.0.0.1:3000/index2.html
or
http://127.0.0.1:3000/public/index2.html
and receiver
ActionController::RoutingError (No route matches [GET] "/public/index2.html"):
how do I get the html from the server
how di I make it the default.
Thanks.
EDIT : thanks for your answers. I am looking for the simplest way to work. in many tutorials it says you can put it in the public folder and thats it. This will same me useless controllers.
You can do that in several ways : the more obvious would be to have an action in one of your controller (or a new one, whatever) that does nothing (except render the view), and add a route to it. There is other ways to achieve this too, with more adapted tools. I never used any of them, so might want to google it (static page rails), but I know one of them is a gem called High Voltage. Hope this serves you well.
I think you might have mis-understood Rails...
I have never used it but I think I can probably help you with your answer. Rails is the most popular MVC framework for the language Ruby, hence 'Ruby on Rails'. Here is a link to the MVC framework this may help you understand it:
http://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller
With the MVC framework you can't 'get' a file directly through the URL. You have to get it through the routing engine. Usually you do this through a Controller which renders a view, typically, from a model.
It's difficult to explain if you don't understand how the MVC framework works but once you have an understanding you should be able to develop web applications very rapidly.
Have a look here for creating your first rails app:
http://guides.rubyonrails.org/getting_started.html
I have a Rails app which implements a web service. I'm not sure how to best write tests for it.
It has one controller. Each method provides json output. As far as I can tell, functional (views) tests would be the right thing to use, but they seem to only work with HTML.
i think that you could be good with using a library like json_spec.
in combination with cucumber this could also server as a documentation for your api-users. have a look at this nice blog post using json_spec.
Our new iPhone project consists of a native app and a server it needs to communicate with. I'd like the server to be written in Python/Django.
The last time we created something similar, the server was in written in asp.net and it exposed relevant methods as a SOAP-based web service. This was very convenient, since we were able to generate almost all server communication code from the WSDL using http://sudzc.com/. Now I basically want to do the same, but with Django instead of asp.net. More specifically, I want to expose methods and objects over an API and I'd really like to have some automatic Objective-C code generation at the other end.
I've looked at a few libraries for Django that are supposed to expose RESTful APIs, and most people seem to recommend django-piston or django-rest-framework. Will either of them have a WSDL-style description that I can use to auto-generate ObjC-code, though? Is there another set of tools for achieving what I'm after that I should be investigating?
In my personal experience I don't know of anything that exists to generate client-side stubs in Objective-C for a REST service. However, there's a very good library called RESTKit that features a JSON or XML to object mapping layer, and nice features like CoreData integration and local caching. There are number of useful Stackoverflow questions on it.
So that can get you part of the way, since it will handle communication and object mapping. If you need to build code-generation, it could output code that sets up RESTKit's mapping structures.
Another REST client lib for iOS that I like a lot is LRResty, for its clean API, but it's lower level than RESTKit in that it doesn't have any built-in parsing/object mapping features.
In this similar stackoverflow question there's a link to something called wsdl2objc which sounds like it's in line with what you need on the iOS side (I've no personal experience with it, so ymmv, etc...)
I have planned to write my own light weight MVC for PHP, that will be used as base for my sites I develop. I have no problem with PHP, OOP, et al. I have trouble on how to actually load Models In controllers and use them amd loading Controller values into Views. In short, I don't know how M-V-C interact behind the scenes.
Any tutorial (concentrating on that) or any contribution is welcomed!
Thanks!
ASP.NET MVC is open source: http://aspnet.codeplex.com/releases/view/58781
Edit: consider this: I believe you are trying to reinvent the wheel, thinking that those MVC framework out there are heavy and packed with uncessary features (acording to your double use of the word lightweigth). In my experience, I always ended up coding those extra "features" because a framework is required to evolve. Loading models In controllers, using them and loading controller values into views is just the begining. If you want to get started eventually, it would be a better investment to write some helper classes and methods: a popular pattern in the MVC world. Unless you are writing a MVC framework from scratch for fun and I am totally wrong (you said you needed a base to use for your sites ).
Best of luck!
Codeigniter is an open source MVC framework of php.
http://codeigniter.com/user_guide/overview/appflow.html
The major in MVC is first of all your controller class initiated and then calls view.
After google and check how other MVC works I decided to take this route. I redirect all my requests with .htaccess to index.php. Then there I define base paths. After all the definitions I include the core.php which in turn includes all core files to my mvc framework. Then in the same file I create Instances of Registry and router and the game starts from here!
Internals are a bit complex now but that is what I ended with!
I know this question is too wide to be answered with a simple "use this framework", but I would really appreciate your advice on that one.
I'm looking to make a (quite complex) project than will run over an API. I'm open to any programming language (PHP, Python, Java mostly) and found many frameworks that are more oriented to make a RESTful web server.
The only major constraint I have is that I would have a reusable, simple and not-code-spaghetti independent package in order to improve my API later easily or even switch to an other framework with no pain.
For Python & Java, I thought about making a dedicated package. Each action would call the dedicated method in the package, the package would return object/dict and the action would transform it to the proper format.
After many research, I hesitate between two framework that could be good for my work but I need your advice because I wouldn't make any mistakes here.
Play! Framework (Java)
Pros :
Router are RESTFul oriented (you define the method (GET, POST, etc), the request and the class.method to use)
You don't have to make one class per action
Cons :
The Model is already included. If I later change the framework, maybe I will be stuck with it (but apparently not since Play! seems to use JPA)
Maybe the fact that if I want to send parameters to the action that would be defined in the method signature, I have to adopt the ClassName.properties instead of a json like {ClassName: {properties: 'value'}}
Tornado Web (Python)
Pros :
Seems to be very powerful : used by FriendFeed (at least) !
Auth via major OpenId, OAuth and Facebook already implemented
Very light (could be a problem)
Cons :
Not so popular : you understand better the work by going into the code than the doc
Urls seems to be very basics (As far as I saw it, you have to define all the urls in one file, with all the class included)
One Class per action (that could be heavy)
Decorators for the basic (testing if user is auth, etc) must be made
For using them in production, it would be easily possible with apache & mod_proxy or nginx.
So, my questions is quite simple : what would you choose (between those two or others, I'm not closed to suggestions) and why ?
Thank you really much for your advice!
My favorite RESTful Web App development framework is Restlet. It's a Java framework/library (it can be thought of as either) but it works well with Jython and JRuby, so if you prefer those languages you could still use it. I mostly use it with Groovy.
I prefer Restlet because:
Its API fully embraces and aligns with RESTful paradigms, so it encourages you to work RESTfully. For example, when a Router routes a request to a ServerResource, it creates a new instance of the ServerResource for every request. This encourages the implementation to be stateless. And there's a rich class hierarchy with all the concepts required to implement a RESTful web app: Client, Server, Protocol, VirtualHost, Request, Response, MediaType, Status, etc.
Its API includes classes for writing both servers and clients, and they're very consistent and almost symmetrical. For example, there's a ServerResource class and a ClientResource class. ServerResource.get() and ClientResource.get() both return a Representation. The only difference is that you implement ServerResource.get() and generate a response representation, while you call ClientResource.get() and receive a response representation.
The API is consistent with Java conventions. For example, if a request made with ClientResource.get() receives an error response such as 401, a ResourceException will be thrown. And if you're implementing a ServerResource and want to return an error status, you just throw a ResourceException (which is a RuntimeException, which is nice).
Via its extension mechanism, it plays very nicely with a broad array of the best Java libraries around. Extensions are included for various HTTP client and server libraries, databases, templating libraries, security libs, data libs such as XML, JSON, OAuth, OData, etc., and even OSGI.
Deployment is very flexible. You can embed a Restlet-powered API in an existing Java app, an existing Java Servlet app, or any standard Java Web App (Servlet) server. Or you can build a stand-alone server app with an embedded HTTP server such as Jetty — that's my preferred approach. And because it runs on the JVM, it runs on almost any hardware or OS.
It's mature, reliable, responsibly maintained, steadily improving, and well supported both by the community and commercially.
It's open source, and has very clear and well-structured code. The developers are happy to accept any contributions. I've submitted a few patches and had them committed to trunk quickly with no drama.
Other options I'd suggest would be the Python microframework Bottle and the Ruby microframework Sinatra. They're both simple, straightforward, lightweight, and effective. And because they work with the WSGI and Rack stacks, there's a rich set of "middleware" modules which can easily be used with them.