I am new to drools. How will i integrate my drool rules with front end jsp ? For example: i have created a front end page registration page through jsp. now how will I apply rules on that page. Please Suggest with through this example that how will it be done
This question seems rather broad in the sense that it's not clear whether it's asking how to write a web application or whether it has anything particular to do with Drools.
To put it as simply as possible.
Your JSP page should have a form which posts back to the server.
There should be a controller which handles requests from that form.
The controller invokes a service which uses the Drools API to invoke your rules.
The controller takes the result from that service and passes it to a new JSP for rendering as HTML.
Anything beyond that requires you to learn how to interact with Drools via its API. Assuming that you can write code to do that, there's nothing different that you really need to do to use it within your web application. The documentation is here:
http://docs.jboss.org/drools/release/5.5.0.Final/drools-expert-docs/html_single/
In case you're interested in code examples of Drools within a web application, you could take a look at this:
https://github.com/gratiartis/sctrcd-payment-validation-web
Full disclosure - I wrote it. It's a Spring web application providing REST web services which interact with Drools.
Related
To visualize it a bit better, assume this nonsense example:
A simple, freestyle HTML/CSS/JS page is served via an HTTP service in ICF.
The page was populated with data from SPFLI, i. e. an HTML table is displayed showing all the entries from the database table (including the carrid field).
A button is implemented on the page to trigger an event.
An entry of the HTML table is selected. Clicking the button triggers the execution of ABAP code, for example like this: The carrid value of the selected table line is passed and based on this value, some ABAP code should be executed (e.g. a SELECT on SFLIGHT/SCARR based on the passed carrid value is executed to populate another table on the page or whatever).
These are my questions:
Is something in this direction possible at all?
If not such a freestyle HTML/CSS/JS page, what would be the best technology to do it (UI5, Webdynpro ...) to do further research (Note: it is not meant for a "productive app", rather playing around)?
Are there any recommendations for demos, tutorials or links especially concerning the ABAP code execution triggering and value passing?
If you want a web application to communicate with an ABAP backend, then you would usually do that through a webservice exposed by the application server.
There are several ways to implement webservices in SAP ABAP. The classic way to do that would be an enterprise service. But the current state-of-the-art would be an OData-compliant webservice with the RESTful programming model.
The web frontend could be implemented via UI5, which offers really elegant ways to bind UI controls to a data model backed by an oData webservice. But if you don't want to bother with the huge dependency and arduous learning curve of SAPUI5 / OpenUI5, then you can just as well communicate with an oData-webservice via the usual vanilla-JS tools (XmlHttpRequest / fetch(url)).
I have developed one spring based java web application. In my project it is requirement to use alfresco as a CMS. For this I want to integrate this application with alfresco. So I decided to use alfresco java API's.
http://dev.alfresco.com/resource/docs/java/
But I am not getting how to use those API's to complete backend work of my web application. Suppose I would like to submit one form having user name & password fields in it. After click on submit button how can I handle request in backend so it will use Alfresco java API to process request and store details in database.
I have to do many operations in my project like upload file, play with documents, Submit different forms. view those forms etc.
My first question is am I going in right direction by using alfresco java API's. if yes then how can use those API? is there any other way to do this?
Any help would be appreciate!!!
Thanks in Advance,
Kailas Salunke.
Well, based on my experience, Alfresco is an excellent ECM but not suitable for being a CMS.
Apart from that, it is difficult to give suggestions, starting from the very general overview you have given, but things like user name and password have little to do with an ECM and storing of data in a database.
You have two options available.
One involve using the Web Content Management Quick Start, it's a Spring Surf app you can (not easily in my opinion) customize for your needs.
The other solutions, if you have an existing web app, rather than develop your own API have a look at CMIS, I have put a simple wikipedia explanation, you can dig further from there.
Then, when you are ready, have a look at Alfresco CMIS first, and the most used Java API for doing CMIS call, which is Apache Chemistry
CMIS, in its intent, guarantee that Alfresco could be replaced with any other CMIS compliant ECM. You can easily integrate Apache Chemistry in your Spring app.
I know the question is about solving the problem probably by different approach but let me specify in details what I want to ask and how much I understand about it.
We have two mvc approach used in ATG(or many other framework) pull based and push based.
As I understand it formhandlers and droplet both are playing the part of controller in different need, repositories are our model and jsps are providing views..
And if i am right till this point then what purpose the servlet chain is solving?How it fits into this picture of MVC?
Please If possible explain with the help of flow diagram from request to response (end to end).
Thanks a lot in advance to experts.
Please help.I could not find this kind of explanation anywhere.
The first thing to remember with ATG is that it is an old platform. So when trying to understand the different mechanisms through an MVC lens, remember that nothing was designed with MVC in mind-the platform predates widespread knowledge and acceptance of the MVC pattern in web development.
Droplets are a generalized mechanism for invoking Java code from a JSP (and previously, JHTML) template. The closest analogue in J2EE-land would be tag libraries. So you can use them to accomplish many different tasks. You can also use them as a poor man's MVC controller. This is done by coding a custom droplet class dedicated to handling the business logic of your page, and setting relevant page state as request parameters. Then you invoke the droplet as the first step in your JSP page. This is not very different from J2EE model 2 with the odd quirk that first your compiled JSP begins executing, then invokes your "controller" code and then resumes with processing the "view."
Form handlers, as the name indicates, are designed for processing form submissions. These are executed by a link in the servlet pipeline (DAFDropletEventServlet), before the page which was posted to begins rendering. Typical usage with form handlers is that they will send a redirect after executing, and cancel rendering of the page, which will abort any further processing by the servlet pipeline. Form handlers are the closest thing to a "controller" ATG provides. But they are awful for handling GET requests and result in some very unfortunate URLs when used for this purpose.
Why did they create two different mechanisms? Why have they not subsequently introduced an updated MVC model as part of the platform? These questions I cannot answer.
ATG, at the page rendering level, is not MVC. Don't look at it as MVC. ATG, at its core, is an extension of the basic Servlets API.
Forms and form-processing, with the successUrl and errorUrl is kind-of MVC. Droplets certainly are not.
It is perfectly acceptable in an ATG application to be fetching data as the page is rendering (i.e. Droplets)
I have an idea to add a edit-layer to website as a Plack middleware.
Explanation: let's say, we create a website, based on some framework and templates and CSS (requesting it like /some/page). Now we could create a middleware so that every request to pages starting with adm (like /adm/some/page) shows the same page, but adds a layer for content editing. So we could easily look and use the page as visitors do, but with double-click on block-level element we could modify or add content. So middleware should bind certain block-elements with certain events (double-click) and set handlers too (with some Javascript library).
For now it is just an idea and i have not seen such approach in any CMS. I am looking for hints and ideas and examples, how to start and implement such system. I hope, there is already done something like that.
You could do it, but I don't think you want to do this. My understanding is that Plack::Middleware's are supposed to be generic, and implementing a CMS as a plack middleware limits its re-usability, and its out of place, there is no inherent connection between a middleware and a CMS.
See these as examples Plack::Middleware::OAuth, Plack::Middleware::Debug, Plack::Middleware::iPhone, Plack::Middleware::Image::Scale, Plack::Middleware::HTMLMinify
It would be trivial to add a middleware filter to insert a form in your html based on /adm/ or /admin/ or whatever ... and mapping the url to the dispatch would highly depend on the underlying CMS model/view/controller framework, which is why frameworks such as Catalyst, Mojolicious and other already provide this feature
See http://advent.plackperl.org/2009/12/day-23-write-your-own-middleware.html
Basically, I think this is a job for a view/controller of your application, a plugin, not a wrapper for your application (middleware)
I know my explanation is lacking but hopefully you catch my drift
I want to develop a Web Application by combining Spring Framework, GWT, Servlets, JSP........
I plan to develop Server side using Spring,Servlet ,JSP....
And for Client side, GWT....
The Output page(Response page) of my Application, will given by JSP only....
Then what is the use of GWT at client side....
please clear my doubt....
Read the following
1) AJAX - http://en.wikipedia.org/wiki/Ajax_(programming)
2) RIA - http://en.wikipedia.org/wiki/Rich_Internet_application
3) GWT - http://en.wikipedia.org/wiki/Google_Web_Toolkit
The problem with using purely jsp to create a web application is that each user interaction typically requires the entire page to be reloaded. Depending on what you're doing this approach is considered outdated. GWT is built on top of javascript and xhttp requests, allowing user interactions to affect only relevant portions of the page. This generally results in a faster and smoother user experience.
If you have already decided that you want to use JSP, then you don't need GWT. Although you could use it to create custom dynamic components and embed them on your page. Or to create a part of your application where you find JSP not sufficient (which would be probably a part that should be more 'dynamic' and would require a lot of javascript).
http://code.google.com/webtoolkit/overview.html#how