I am very new in AJAX/JQuery. I have problem with following thing. I am hoping to get some information and suggestion on following thing.
I have data real time generated data (eg. xyz) in my localhost server which i have programmed using Java.
My question is
Is it possible to retrieve this data ( i.e. xyz) from localhost server using AJAX/JQuery to JavaScript????
What function does that and how do we do that ?? Plz show me with example..it will be very great help for me
Ajax is something just like common HTTP requests, but it is sent inside your jvascript code and can be moderate with javascript.
Independent of the server side script you have, you can use Ajax to send requests and get responses from that server side application (In server side it can be treated as a simple HTTP reauest).
Finally this is a helpful toturial: W3School Tutorial , and if you are familiar with JQuery or using it in your current project, it is the reference for JQuery Ajax: JQuery.ajax, both with samples.
Related
So, I'm currently developing an app for a service which has a json-based (unfortunately) read only API. Retrieving content is no problem at all, however the only way to post content is using a form on their site which location is a PHP script. The service is open source so I know which fields the form expects, but whatever I send, it always results in a BAD REQUEST.
I captured the network traffic inside my browser and as far as I can see, the browser constructs a multipart form request, however when I copy the request and invoke it again using a REST client, a BAD REQUEST gets returned.
Is there a way to construct a http request in Android that simulates a form post?
If it's readonly I think you wouldn't be able to make requests with POST (it's assume for editing or adding things).
If you let me make you an advise, I recommend you using this project as a Library.
https://github.com/matessoftwaresolutions/AndroidHttpRestService
It makes you easy deal with apis, control network problems etc.
You can find a sample of use there.
You only have to:
Build your URL
Tell the component to execute in POST mode
Build your JSON
As I told you, I don't know even if it will work.
I hope it helps!!!
I'm developing a web app using JSTL and Javascript in Eclipse Juno. I've been reading questions like How to set the JSTL variable value in javascript? and my code works good even if I have error in eclipse:
But... Is it a good practice to use JSTL and Javascript like this?
Does it cause a low performance in the time of rendering the webpage?
Can this be done in other way?
Is it a good practice to use JSTL and Javascript like this?
It is not bad practice or good practice. The bad practice would be using JSTL to control the flow of JavaScript, which is plain wrong because JSTL runs on server side and JavaScript on client side.
Does it cause a low performance in the time of rendering the webpage?
JSTL will only help to generate the HTML for the current view. JavaScript is not involved in the HTML generation at server side but at client side unless you work with nodejs or similar technologies.
Can this be done in other way?
This depends on what you're doing. Common way to access to data when accessing to a web page:
Application Server (AS) receives a GET request on http://www.foo.com/bar
AS pre process the GET request (load data from database or another data source, pre calculations, etc)
AS creates the response for the GET request (apply the data to generate the HTML)
AS sends the response to the client.
The browser client renders the HTML.
Another way to do it:
Application Server (AS) receives a GET request on http://www.foo.com/bar
AS creates the response for the GET request (generate the HTML which contains JavaScript functions to load the data in the onload event).
AS sends the response to the client.
The browser client renders the HTML.
The onload event fires and load data in the onload event through RESTful services. This way, the data interaction is handled in client side only, but the data comes from server side.
These are two very simple alternatives to handle the same problem. Which one to choose and work with will depend entirely on your design, there's no definitive answer.
I a deveveloping a web site that comunicates with a custom made webserver by me in Java. The web site is made in PHP/JavaScript/JQuery running on Apache and i made a simple second webserver in Java to support some designed features by me, and this server runs under another port XXXXX. The problem is, i want to make requests in jQuery to second server the domain is diferent, the page runs on domain and the $.getJSON function calls domain:XXXXX wich is not allowed. I thought user $.getJSONP but im concerning concerned issues. The connections between two points is authed (i was think by passing a token beyond the callback generated by jquery). The two poins are supported by. Is there safe in this case use $.getJSONP or exists other alternatives thinking in browsers support(IE7+ and FF3+).
Sorry for my english :)
Best regards lealoureiro
JSONP should work for your needs, however your other option would be to have a proxy service on your second server that would make the request server side. Your client-side code could then access all the data natively via json instead of jsonp.
I have some GWT application that run on the server.
we are subscripting with some solution that pings this application in a regular interval of time.
The point is, this solution (service) checks the returned response from the server to contain some pre-defined keywords.
But as you know, GWT return plain empty HTML page with the data contained in the .js file.
So, the Ping service will not be able to exmain the pre-defined keywords, Is this statement true??
And if this is ture, cannot we find any workaround solution to solve such problem?
Thanks.
The problem you are facing is related to the crawlabitlity of AJAX applications - Google has some pointers for you :) Generally, you need a headless browser on the server to generate the output you'd normally see in the browser, for example see HtmlUnit.
Only the initial container page and the loader script that it embeds are HTML & JS. Afterwards, you use GWT's RPC mechanism to exchange Java objects with the server, or Ajax (eg. RequestBuilder) to exchange any kind of data with the server. you name it: JSON, XML, plain text, etc.
I have a simple Java client application (Android app). I have to write a PHP server application which receives a request from the Java client application to write some data to a MySQL database or read some data from the MySQL database. It should respond with a status message (Write failed/success) or the data requested respectively.
How would I get the Java client send a request and receive the reply from the PHP program and how would the PHP program receive the request and send the reply? I have googled about SOAP and REST architectures, but looking for a simple tutorial which will allow me to implement this simple program.
Thanks.
With basic Java SE API you can use java.net.URLConnection to fire a HTTP request. A basic example of firing a GET request can be found in Sun tutorial on the subject. A POST request isn't much different, you instead just need to set URLConnection#setDoOutput() to true and write the query string to URLConnection#getOutputStream() instead of in URL.
Note that it's "lazily executed", the request will only be fired if you actually obtain the response stream by URLConnection#getInputStream(), even though you don't need it.
If you want less verbose code and/or more control over the request, then I can recommend to use Apache Commons HttpComponents Client.
The PHP program in turn can just be written the usual way. Get request parameters by $_GET, $_POST and so on and echo the response. Nothing special needs to be done here. You may however consider to use an more easy parseable response format, such as XML or JSON.
You should build a simple JSON or XML based REST web service with PHP.
Then with the Android SDK, you can use the HttpClient module to connect to your web service. The SDK also provide a JSON and XML module to parse the result.