I want to create a program using Java for Automatically copied USB's data when it's insert to machine. How I do it?
There is no such thing as "USBs data", the very concept doesn't exist.
There is nothing specific in Java SE for do this job.
I may think of two ways to get that working:
Write a Java program that starts on boot (maybe a service), the prog scans continously available "drives" (D:,E:,F: ... in Windows, mount on Linux), the USB flash may be marked with a specific folder/file name (eg. COPY_USB_). That can be done with the File class.
Write a Java program that get invoked on plug-in. I know that can be done on Linux with hotplug-script support.
Related
I have some mex files that urgently need to be called via MATLAB, there is currently no way around. However, I really despise MATLAB's GUI (in)possibilities and would like to create some e.g. JavaFX Apps.
My question: how can a Java app's communicate with a running MATLAB instance?
I know that you can include Java objects into MATLAB, however I would prefere to have a standalone Java app.
Java can execute commands via command line for example:
Process process = Runtime.getRuntime().exec(command);
process.waitFor();
So it is possible to execute a MATLAB script via command line in Java.
In MATLAB it is possible to write files with any data needed. I don't remember the exact way you may do this. http://www.mathworks.com/help/matlab/ref/fprintf.html gives an example:
x = 0:.1:1;
A = [x; exp(x)];
fileID = fopen('exp.txt','w');
fprintf(fileID,'%6s %12s\n','x','exp(x)');
fprintf(fileID,'%6.2f %12.8f\n',A);
fclose(fileID);
It is some kind of a workaround but it should work and it is not really hard to implement.
Update.
If Matlab is already running and you want to communicate with it in another application (Java), it may be done using a network connection through the localhost. Matlab may listen to some predefined port (for code example see http://www.mathworks.com/matlabcentral/fileexchange/11802-matlab-tcp-ip-code-example ) and do some action when a "start" trigger is sent via Java (or even some data along with the trigger). In Java you may use the Socket class (some code example may be found here http://www.javaworld.com/article/2077322/core-java/core-java-sockets-programming-in-java-a-tutorial.html ).
Also it may be done writing data into files. For example, Java adds some command to some file with predefined name (command.txt). Matlab scans this file in a loop and when something is found there it starts calculation (and Java application waits for results in some results.txt file).
I would suggest to start a server in Matlab that listens on a specific port to send/receive data to/from a Java client. By using the eval Matlab command you could even invoke scripts/command/etc. remotely controlled by a Java client.
You might want to have a look at this code example.
I have the following problem:
I have a shared folder on my computer(Windows OS). I need a script in Java that when runned blocks the acces of network users to this folder so that I am allowed to modify its content.
Any suggestions or ideas?
If you are using Java 7 or later, you could use the java.nio.Files.setAttribute to set the DOS permissions using the relevant attributes from the DosFileAttributeView.
(You might also be able to do it using AclFileAttribute or PosixFileAttribute ... depending on the true nature of the folder you are attempting to modify.)
For Java 6 or earlier, you would need to resort to a 3rd-party library, JNI/JNA calls, or using Process to run an external command.
I want to know how to make a java program that can be used to open stuff up. Ex: notepad++, win zip.... Do I have convert the jar to .exe first? Also, does the file chosen get passed in to String[] args?
By the way, I know that it works with cmd but thats not what I'm asking.
Depends on the OS. Under windows, you need to attach some details into the registry.
Have a look at the 3rd answer in Utilising a file association in a Java application for an example?
You could also have a look at http://www.rgagnon.com/javadetails/java-0592.html
UPDATE
Also, when the OS executes the program, you should receive the file as a command line parameter through the main method
I don't know if this will work suit your needs or not, but you could also take a look at File association in Mac
There's many choices on how to make a Java program runnable. Like you mention, the simplest choice is to use the command line. If you want to make it work with most OS's GUI interfaces (and the Open With dialog) the easiest choice is to make an executable jar. IDEs can make this very easy for you, in Eclipse just right-click on the project and select Export > Java > Runnable JAR file.
Another excellent option is to turn your application into a Java Web Start application, which lets users easily run Java programs being served up online.
Alternatively, like you mention, you could convert it into an .exe file:
Compiling a java program into an executable
How do I create an .exe for a Java program?
How can I convert my Java program to an .exe file?
Deploy the app. using Java Web Start.
JWS provides many appealing features including, but not limited to, splash screens, desktop integration, file associations, automatic update (including lazy downloads and programmatic control of updates), partitioning of natives & other resource downloads by platform, architecture or Java version, configuration of run-time environment (minimum J2SE version, run-time options, RAM etc.), easy management of common resources using extensions..
Here is a demo. of the file services in which the app. is associated with the file type .zzz.
..does it get passed via the windows file chooser?
No. It gets passed to the main as either -open filename or -print filename. What the app. does with those strings is up to it. The demo. linked above will prompt the user in the sand-boxed version, simply because it is sand-boxed. The other one should work without showing prompt or dialog.
I have a program, written in Java, which originally used its directory in Program Files to write files accessible to all users of this program. This required our users to run as administrator all the time. In an effort to alleviate that, we decided to move files which needed to be written during regular usage to the ProgramData folder using the %ALLUSERSPROFILE% environment variable. Using a subfolder in this directory for our application works great if it is designated as writable during the installation process, which works fine using NSIS.
The problem comes with upgrading existing users. The Java File API provides setWritable but this does not appear to work after testing on development machines. It looks as though the new file API with Java 7 would solve this problem, but with no release date on the horizon I would rather not wait.
It seems the simplest solution would be to use JNA to call the appropriate Windows API call to set this directory writable. Since upgrading the software necessitates admin rights, similar to installing, it should let this change go through fine. However, I'm unsure where to start, having never used JNA before or the Windows API. Suggestions as to which Windows library to load and what functions to call would be appreciated, especially if someone has encountered a similar problem before.
Well, I'm glad you gave some background...You could use JNA, but the easier way would be to execute a call to the command-line utility cacls. It's included by default in Windows XP installations, I believe, so it should do the trick for you. Try Runtime.getRuntime().exec("C:\\Windows\\System32\\cacls.exe"+options)
Check out the documentation here -> http://technet.microsoft.com/en-us/library/bb490872.aspx
I use the follow line:
Runtime.getRuntime().exec( "C:\\Windows\\System32\\icacls.exe \"%ProgramData%\my application" /grant *S-1-5-32-545:(OI)(CI)(W,M)" );
S-1-5-32-545 is the SID for BUILTIN\Users because the name work only on English systems. https://support.microsoft.com/de-de/kb/163846
This give the BUILTIN\Users write access to all files in the given directory independent which user has create it.
I want to get the name of all active process on a Win2000 machine. I know that "tlist -s" is the command, but to use this, the "tlist.exe" has to be extracted from the Win2000 CD-ROM. I also know "tasklist" only works on XP or greater.
I am running my tests on VM Ware, and do not have a CD-ROM. Is there another way to programmatically get the task list on Win2000?
I ended up just using JNI to handle this case across all platforms that I needed. Refer to another post of mine (which was trying to use SWT to obtain this list, but it gives a good JNI downloadable example that is useful):
Get task manager list via SWT?
In Java without calling a 3rd party application (like say PsList)? Not without JNI.