I have an app in android,a kind of client-server in which the client has stored some gps data in Sqlite database and once connected with server it delivers it that data which at its turn stores it in it's own database for future manipulation!
Now the problem is that I have to create a server that accepts multiple clients and I cannot find a decent example in this way.I'm not using no services in combination with it!
Both my client and server are on android!!!!
I have already did the connection between client and server,but only with one thread(I mean my server can accept only one client at this moment!)
Is this suitable?
How to implement simple threading with a fixed number of worker threads
Thank u in advance!
If server is Microsoft based, .net web service can be used that can be accessible from multiple Android clients and work with database.
Your server is not on the Android device I guess, so I don't think the question is android related.
Check out this example of multithreaded server in Java and this one as well.
To communicate with database, see the Java JDBC tutorial.
Those examples are in Java, because that's what I am used to, but any other language will fit as well.
A simple POST request from the client to the server should be good enough. Encode the data in a suitable format (JSON/XML) and send it as a POST HTTP request.
I don't understand why you want to write your own server. I would just use a PHP/Python script running with Apache to receive the POST request and store the data in a database (MySQL, PostGre).
On your Android device, you should put all your code in an AsyncTask. Android uses the standard Apache libraries to make the HTTP request.
Related
I'm currently developing a Field-Service application that stores data in the local sqlite database on an android device. At some point, usually after completing the data collection rounds, the local sqlite db is to be synchronized to a remote sql server db on the server, also i need to update some local table from sql server db.
Any suggestions as to how this could be achieved or engineered as a solution? Or even better, are there alternatives to synchronizing data in such an application?
I think that the best is using a intermediary like web services or your own TCP based logic layer for your application which would connect to SQL server and execute requests of your applicatation. Don't try to connect to your SQL server directly from Android. You can write
some backend code on your server (or webservice) and then call those code methods from your android device using Http.
And also there are many themes in stackoverflow like your:
How to connect Android to a database server
Connecting android with MS SQL SERVER 2008
About how to write web services. It's a big question, and you must choose technology, there are very many libraries, frameworks and platforms that help you to simply write a web service. You must choose communicating protocol, it may be SOAP, WSDL or maybe remove calling procedure, it may be rest application. If you use java stack, there are some popular frameworks at the moment:
Apache CXF
Spring Web Services
Axis2
You can start from reading what a web service is:
http://en.wikipedia.org/wiki/Web_service
Also some links which provide example of accessing web services from android:
Step by step to access web service from android
Android and soap web services
Accessing restfull web service with android
Another and much easier approach is to use a Virtual JDBC Driver that relys on a secured three-tier architecture: your JDBC code is sent through HTTP to a remote Servlet that filters the JDBC code (configuration & security) before passing it to the MySql JDBC Driver. The result is sent you back through HTTP.
There are some free software that use this technique. Just Google "Android JDBC Driver over HTTP".
You would have to keep a middle tier online server.Which may communicate to and fro between your application and MSSQL db.May be servlet or a request handler which synchronises between the SQLite and SQL Server db.
I'm new to Android and to web services in general.
This is what i gotta do: My company has a back end website(for the client to monitor the sales) that's used to manage/monitor sales on some stores and it connects to a MySQL db to store data about sales and users(usernames and passwords).
What I want to do is to get data from that database and to add (sync operations) new rows, all of this from my android app.
I googled this many times and it came up with some similar projects but using another languages.
I would like to see some code samples if possible and some how-to theory, what theory should I follow when developing this, how and what ways of communicating between android and python web services and from the web services to the MySQL database.
Thank you in advance.
You will need a working API, that allows you to communicate to the web service from the android application. I would read into how to write an API and how to build a RESTful service using JSON as a way of communicating between server and android app. There are alternatives to JSON, but JSON is better suited for Android than perhaps AJAX and soap is being used less and less. (Can ajax call be done in Android? It can but has limitations)
(I could only post two full hyper links as i don't have enough reputation yet to do so, you may have to remove the spaces)
API:
http://sharismlab.com/blog/2012/07/21/how-to-write-an-api-for-your-web-app/
REST:
www .restapitutorial. com/lessons/whatisrest.html/
JSON:
htt p:// www.r evillweb.co m/article s/why-use-j son/
You may want to check out restjee. It allows you to define and implement RESTful data access APIs without having to write any server side code. Works with just about any database.
I am trying to learn to implement android apps to get news, promotion message, and calendar from server. What is the best and easy way to communicate with database server? using JDBC or other methods?
Thanks
Using JDBC?:
In the words of Commonsware:
Never never never use a database driver across an Internet connection,
for any database, for any platform, for any client, anywhere. That
goes double for mobile. Database drivers are designed for LAN
operations and are not designed for flaky/intermittent connections or
high latency.
On the client side (Android app), you can use SQLite to store data locally. It might not be necessary at all actually. For instance, it can be used for offline features, search, etc. For client-side, read up on this simple post
On the server side (whatever server side technology you know or want to learn), you can use whatever language, whatever database on whatever server OS you want. This part is commonly called the back-end, which will store your data while your app communicate with it through HTTP.
You can use json to parse data between server and the android device. In the server you can use jdbc with json if you are using servlets in the server.
To communicate between a server and an android device you can use JASON. See following links for some help.
http://www.androidhive.info/2012/01/android-json-parsing-tutorial/
https://www.learn2crack.com/2013/10/android-asynctask-json-parsing-example.html
https://www.learn2crack.com/2013/10/android-json-parsing-url-example.html
Also in the device to deal with data within the device you can use SQLite. And in the server you can use jdbc if you are using servelets.
To communicate with Database server You should use web service API such REST , soap
I want to send image and text data from Android phone to a Server. i am new plz suggest me the best and easy way to do this task. Server is running a java web service and i will be getting the data from server and also sending the data to server. Thanks
As your server is already there, you will have to use protocol it can uderstand - also SOAP, REST or whatever it uses. So no choice for you.
If you are deigning client-server interacton with android application, you may consider network socket communuication which has less overhead as webservices.
I'm planning on writing an android app that can view and update data on a local network Oracle DB.
I have already written a python script which checks the oracle db every couple of minutes and writes out XML files which I then plan to parse through my android app to display the data.
As I mentioned though this will only work if the android device is part of the same network (either connected locally or through a vpn), and the XML will be stored on a Unix server.
The question is how to access that Unix server with the android app? Can I use FTP via an android app, or should I be looking to change the python script to send the XML to an easily retrievable location?
EDIT To clarify what you mean, you have a web service running on something like tomcat, the client sends a request to get the data from the oracle db (can also use some form of authentication), the web service responds and sends the data in a format (XML, JSON etc.), the client then sends a request back to the web service to change some data on the oracle db, and in turn it does the clients bidding?
Normally you would create a web service to provide data to mobile clients. There are several reasons for this:
Web services are accessed via HTTP/HTTPS which is a standard protocol and is guaranteed to work on all networks. Corporate wifi networks are especially notorious for locking down protocols except for web and email.
Web services compared to static XML files have an advantage of creating response on the fly. Which means that data will be current.
Web services can take some input parameters and create response based on this parameters.
Authentication: it is a common approach to implement username/passord authentication in the web service, especially if you serve some private data.
Update:
REST is a very popular type of web service. Look at some implementations in Python: Recommendations of Python REST (web services) framework?
This book helped me a lot: http://oreilly.com/catalog/9780596529260
REST is a way of designing your web service. Folks much more intelligent than you and me have divined that all of the work needed for something to work on the net can be handled through a combination of HTTP status codes, HTTP verbs like POST, GET, DELETE, PUT etc. and a clear hierarchy of resources (nouns). It sounds very limiting but it's quite beautiful when it all works together.
Have a look at the Facebook Open Graph API (developers.facebook.com) to get an idea of what a proper REST service looks like.