I have developed an Java Swing Application with MS-SQL Server database and now i want to provide backup and restore option in my java swing application that is on click of a button it should backup the database and restore the database any possibilities of how can i do it through java. please help
Two ways to do that. Backup and restore are just sql commands so you'd do them just the same as as you'd do any other bit of sql, e.g. a sql insert statement, unfortunately you need to know a fair bit about the the system to just do them, and you'll get no progress indicator. Using SQLSMO is another possibility, not sure about hitting a .net dll from java though. You could use SQLDMO (pre.net), but you'll need to install the backwards compatibility tools, and you'll give yourself an upgrade headache as DMO (while it seems to work) is not supported from SQL2012. Both have an event you can tick a progress bar on, course if the back up is fairly quick you could get away with not bothering with that.
However, some more to think about. You can backup while the system is running, but then you'd don't have a clear point where the system was at when you did.
Restore requires exclusive access and a high level of privilege, so it's not something you hand out and you need to get everybody off the databases.
And last but far from least it would be very bad, if you inadvertently restored a version of the database that no longer matched the application....
Personally I'd say the people who were authorised to do this should be able to do it without your tool. Dumbing it down, means a lot of code to make sure they don't restore a sql2000 back up from the trial you put out eight versions ago.
We did something similar back up restore code is a bout 2% of the application. For instance we do a pre-backup check, using dbcc et al, to make sure they aren't successfully backing up a corrupt db...
You can write a simple script to backup your database and invoke it from java.
You really need to put a little effort in here.
Since you can connect to the database server already and send it SQL commands, read this for backing up using TSQL.
For database restore, read this.
You need to have the appropriate permissions and access to the hardware for this to work.
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I have a system in Java where different classes stores different information. There is a main class where the user will input the information of these classes and make them interact with each other. After the user is done, he will exit the system. The Next time the user recompile the project, all the previously entered data should be there. The user can use that same data or add more information.
So Simply, How to pause/save the system on close and resume it when I execute it again?
PS. I can't use Database in this. It must be something else.
The Next time the user recompile the project
Users dont recompile projects. They just run your app.
You keep saying 'not DB', so, then, the answer is trivially: impossible.
A database, by definition, persists some data, hence the name: It's a base of data. If that's off the table, you're out of luck and what you want is not possible.
Perhaps you are careless in your wording there as well and all you mean is perhaps:
I do not want to bother with forcing the user to install a database
Okay, then, don't. Use an in-process database, such as h2. The user doesn't know an SQL-based database system is involved, all they see is a file appear. No extra processes are launched.
I hate SQL
Okay, then, don't. There are tools out there that turn an entire object structure into a bag o bytes which you can then save to a file, for example Jackson which can turn one object (which can contain all the relevant user data if you want) into JSON data, which you can then save to a file, and restore later. Of course, if someone trips over a powercable halfway through writing it, the file is corrupted. There are ways to fix that (save to .tmp, then move it into place, as that's usually atomic), but you're sort of committed to re-inventing the wheel here, due to your insistence you don't want databases.
I just want to save the entire system state
You can't. Not how java works.
Can't I do it with zero dependencies?
There's java's built in serialization system, which sucks, has a list of caveats as long as my leg on how to use it, and is more or less disliked by the maintainers of the java platform itself. This is not the way to go. It also still won't 'save the entire system state', it just saves one object, and does a much worse job at this than e.g. jackson.
I'm trying to develop an application for taking backup for my device. How can I write this? Till now, I've got all the installed packages list and I'm placing 3 buttons for taking the backup(Backup, CheckAll, Cancel).
If I'm going to take backup button it contains one alertdialog it shows 3 options (now, later, cancel). How to take backup the installed packages to one new list and it'll shows by date and time. How can I do this? Any idea?
i don't know if its possible to do that. I remember that i read in an article that in order to access to other packages you need to use the same user that the app does, and from my point of view that means that all the applications that are going to be backed up need to have the same user. I'm not an android expert but i think it wouldn't be possible to gain access to the other packages if you try Java IO to read the files as you normally do.
Good luck, maybe someone knows how to do this.
I don't know what do you mean by backup installed packages.
Generally users keep backup of their database and preferences data.
If you want to take a backup of your database and preference then you can create xml of your database and preferences using xml-serialization.
More information about xml-serialization Click here
And also you can refer inbuilt facility for get backup Click here
I created a small application that, when run, creates or updates some tables in a database by extracting data from some PDF files. Everything works fine in this desktop application, but the next step for me would be to make it possible for an administrator on a website to upload a PDF file and my Java program would then run and update the tables accordingly.
The problem is I have no idea where to start with this (the site isn't done yet, but I'm running some tests and it is going to be coded in PHP). I'd like to know what kind of technologies I need to let the server run the program and update everything as it would in the offline version. Sometimes it takes a while to update everything, so ideally, the user uploading the PDF could continue browsing other pages while the server does its job. (I'll probably implement something that when the server is done processing the file, it says if the program ended successfully or not in a log file)
Can someone tell me what terms to search for on Google or give me some pointers? I haven't chosen where my website is going to be hosted either, so if someone could tell me what to look for to know if they support running applications like this, I'd really appreciate it as well!
This could also apply to other programming languages as I know a bit of Python and C++ as well, so in the future I might have some applications in those languages I'll want to use on the web.
If I'm not approaching this the right way, I'm open to other suggestions, but the best solution would be to keep my Java program intact as I know it works exactly like I want it to and I'd rather not have to start it all over again.
If your host is *NIX based you can use crontab (Automatic Task Scheduler) to run your program at set intervals. Make it check if a "new" PDF exists, and run the program if there is. There may be a way to use Windows Task Scheduler type programs to do it on Windows. This is probably the easiest way.
Alternately you can use You can use shell_exec() in your php to execute a command on your *NIX system directly to run your java program.
Whenever i want to connect to internet,i double click a connection icon(i created it earlier where username and password(for broadband) are stored) and click connect.The icon is in the network places(Windows XP)
May i know how to launch this connection from java or any other language? (I am asking this because my Internet Service Provider doesn't charge anything between 2 AM and 8AM :-) )
Creating a system task to run the program. You shouldn't need Java to execute a program on windows.
To use Scheduled Tasks in XP: http://support.microsoft.com/kb/308569
This is going to be unnecessarily difficult with Java, I believe. You'd have to write some native code to do the job for you, at which point you may as well write your whole program in C# or C++ anyway.
But, since you asked for a Java approach, you might want to look at the Robot class. It lets you move the mouse to a specific location on the screen, click, and otherwise automate the manual actions that you are doing. It's a very fragile solution.
Alternatively, if you can figure out what command the network connection shortcut is invoking, you can directly invoke it from Java using Runtime.exec.
(I don't really see why Java is good for this task, though.)
I am creating an android app that is basically a listing of information on Mushrooms. I get this information from an sqlite database. I have a global singleton with a services class inside it in which I use to access my db. Almost every activity accesses the db. Is it better to leave my db open all the time or open and close it as I need the data?
If the best practice is to leave it open all the time, where do I need to make sure to close it and what is the worst case scenario if I left it open when the activity was destroyed?
Your best option here is to refactor so that your application accesses the database via a ContentProvider. Your ContentProvider implementation is the only thing with a handle to the database open.
This gives you several advantages:
only one thing has the database open, so your problem just goes away.
lots of standard support classes to automate stuff like database management.
better integration with the standard Android list-management views, which are all designed to work automatically with cursors provided by ContentProviders.
All your data can be addressed by URI (typically of the form 'content://com.fnord.mushroom/mushroom/43'), which means that other applications can access your data too.
Using a ContentProvider, it's possible to glue three or four standard classes together to produce a browser interface to your database and never actually have to write any real logic.
On the negative side, ContentProviders only really support access via a limited interface --- in SQL terms, you get INSERT, SELECT, UPDATE and DELETE with no nested clauses. If you're doing complicated SQL stuff it can be a bit painful to route requests from your app to the ContentProvider and back again. However, most people don't need to do this (and if you do, custom intents are the way to go).
I would open the db as needed. That way you know for sure the connection is closed once the particular activity that opened it is finished. Although Android has built in checks to make sure it closes upon application termination, it doesnt hurt to be on the safe side. I'm also guessing having it open all the time could cause leaks or something.
Based on my past experience in Java I would say it is better to close the connection, it probably doesn't matter in a small Android application, but if you have 10 applications running and all of them access the database, you have 10 pending connections. Start a few more and sooner or later another application will have to wait because the SQL server can't handle any more requests.
I guess you could think of it as a file on your computer. You read data from it, and then close it when your done. Why keep a file open in your application?
Now I'm very new to Android programming so I haven't got around to implement database calls. But when I faced the same problem in a Java application a few years ago I implemented a database object, in which I had the connection to the database. "Everyone else" (the classes) had to call the database object (singleton or final methods) to get data, sort of like stored procedures but in the application instead.
Because of this I knew when the calls where made and when they stopped. I then put in a timeout, so as if nothing happened in a few minutes, I would close the connection to the db. (This also took care of some timeout exceptions because the timeout of the connection would never happen.) When a new call entered, I could easily start a new connection and use the new db connection.
Basically I abstracted away SQL calls by having methods as public Fungus[] getAllFungus() and public Fungus[] getFilteredFungus(string where).