I want to find out the recent file used by all applications in windows env using java.
I have tried with
using Registry: I am trying to get the recent file information from HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\ComDlg32\OpenSavePidlMRU. But I am getting some "HEX" value but i am not able to retrive the string equivalent. I have also tried http://code.google.com/p/java-registry/
I have also tried with "recent" file folder. But i am not able get the actual type/path of the file.
Sounds like a job for Sysinternal's Process Monitor (by now, that's official - and free - Microsoft software). First, add a filter of type process name of value "java.exe" like this, then add the "ReadFile" and "WriteFile" operations as additional filters, like this:
Related
I am currently trying to have Logstash work on Solaris with the File Input method. But I am encountering some bugs (see LOGSTASH-665). After digging a lot, it appears that native support for File.stat on my system (SunOS 5.10, JDK 1.6.0_21, 32 bit) is totally deficient, so I am looking for a way to properly handle it.
Specifically I want to access the inode information. Based on the metadata I can gather about the file (like its path and whatever is available on solaris), I want to calculate a number which is unique for that file, and which changes when the file is replaced by another file which has the same name. At first I thought about simply using a hash of the file path and used this function as a replacement, but indeed, when the file is rolled over the number does not change, so I need to also access the ctime information...
..Or make a system call to get the ls -li result to get the real inode number by another way.
Problem is that I never used ruby before, I am more used to java, so I am struggling to find a solution. Every suggestion will be appreciated.
The best solution I know of is to wrap the native call using JNI or JNA.
There do appear to be a couple of projects that have done this, although I haven't used either of them. See this question: Is there a Java library of Unix functions?
For whatever reason, I sometimes need to find the current user's My Documents folder on Windows in a Java program to read some files. But as far as I can tell, there is no way to do it that isn't severely flawed.
The first wrong way: System.getProperty("user.home");
Why it won't work:
It only returns the \username\ folder; I'd need to add "\Documents\" on to the end to get the Documents folder... and that only works in English.
Sun bugs 6519127 and 4787931. Java finds the user home folder on Windows by reading a deprecated registry key* to find the Desktop then taking the parent; this method has multiple known problems that will easily cause a completely wrong folder to be returned. The bugs are 3.75 years and 8 years old with no fix.
The second wrong way: Using a registry-reading program to get the Personal folder of the user, which is My Documents (but i18n'd).
Why it won't work:
While it fixes the English-only problem, it's still using the same deprecated registry area, so the bugs still apply to it.
The deprecated registry key says to use a native call (SHGetKnownFolderPath) which I obviously can't do from Java.
The third wrong way:
JFileChooser fr = new JFileChooser();
FileSystemView fw = fr.getFileSystemView();
File documents = fw.getDefaultDirectory();
Why it won't work: It works great!
Except when it doesn't. While I had a program that used this open and running in the background, I opened a DirectX game (Fallout: New Vegas). The Java program immediately terminated with no stack trace. Always reproducible (for me on that game, and who knows what else). Couldn't find a Sun bug#.
So is there any method to find a user's Documents folder, on Windows, from Java, that doesn't have known problems?
(This is a nice big question.)
*(The key is "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders")
There's no pure java way to do it, but you could use the JNA wrapper over JNI to do it without having to write any native code yourself. There's a good example of how to get the Documents folder on Windows halfway down the responses at:
What is the best way to find the users home directory in Java?
A time consuming, but reliable way of finding the 'Documents' folder of a windows user: Make your java app execute a bat script that uses Reg.exe (a windows system file) to find the value of the reg key which has the path in it. Then use a pipeline in the same bat file to send that data to the 'findstr' function which windows command prompt has. Use another pipeline to output the returned value to a text file. Then, simply make your java app read that text file, and delete it once its done :) Worked well enough for me.
Code for the bat file:
# echo off
Title Find Documents Folder
Reg Query "HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders" |findstr "Personal">>DocPath.dat
exit
There is a custom Java API that someone built (their website no longer works), but there code remains on Google Code:
http://winfoldersjava.googlecode.com/files/WinFoldersJava_1.1.zip
There are two DLL's that need to be referenced, one for each architecture(x86 and x64).
user.home is not "my documents", but users home folder, like on Unix ~/.
To get to "My documents" you can use System.getProperty("user.home")+"\Documents"; irrespective of the language system. Try it.
I have an application that is started with JWS. The first time user launches this application he has to choose a path where Berkeley DB XML is installed. I do need this to set the native library path and restart the application with -Djava.library.path parameter. Berkeley DB XML java bindings uses JNI to make calls to the database. Since our users may have different OS I cannot rely on a default location.
So, I have a problem with getting current classpath. When I print out "java.class.path" it only gives me "/System/Library/Frameworks/JavaVM.framework/Resources/Deploy.bundle/Contents/Home/lib/deploy.jar". I have three jars that I cannot find in my sys props.
on my Mac.
I hope this was understandable and thanks for any tips beforehand.
Try to repaire permissions with DiskUtil.
Avoid using this pattern. What you could do is to store the command and execute that simulating that you are starting a new process.
I am in the process of writing a cross platform Swing based application in which I want to utilize a file association which has been registered with the OS.
So iv got to the point where I can click on a file and my app loads, but what I need to know is how I can get my application to know where the file is that launched it and then query the contents.
Is there something further I have to do with the file association registration? Or can Java do this for me?
I'm not positive, but I'd expect that the name of the file you're processing by file click will end up in the arguments to your main() method. Have you tried/checked that?
If this is on Windows (you didn't specify):
In the registry wherever you specified your application path for the file type registered to it, add to "%1". This is a special parameter Windows will fill in with the path of the file that was clicked. So your registry entry would look something like c:\path\to\app.exe "%1"
One way to do this is to have the file association run your Java app via a script or batch file, and have the batch file pass the pathname of the file as a command line argument, environment variable or Java property.
Extensions can be linked to applications, you can setup the registry keys during installation. Which keys you need is documented here:
http://support.microsoft.com/?scid=kb%3Ben-us%3B185453&x=6&y=11
From java you can't access the windows registry in a direct way.
Using Runtime you could do something like that
http://www.rgagnon.com/javadetails/java-0480.html
There're two commands on Windows that can help, assoc and ftype, so that you needn't do the dirty laundry to manipulate registry. Invoke the commands using, say, java.lang.Process. http://www.rgagnon.com/javadetails/java-0592.html
My Java application is saving stuff in 'user.home' but on windows this does not seem to be the correct path to save application information (as a friend told me). An other option is using the preferences api but it's not possible to set up the hsqldb location using the preferences api. Also, I want all files to be available in the same folder (local database, config, cache, ...).
I'm looking for some example code or a framework that takes care of os-specific stuff.
On my WinXP Pro SP3 system, user.home points to C:\Documents and settings\<username>
Lot of applications just store their data there (instead of this path + Application data, but some others go down to there), creating a directory in Unix style, ie. dot + application name (examples: .antexplorer, .sqlworkbench, .squirrel-sql, .SunDownloadManager, .p4qt, .gimp-2.4, etc.).
Looks like a decent, common practice...
It's unusual for a window app to save data in user.home but not "wrong". Windows applications love to spread their data all over the place (a bit in the registry, a bit in the application's install directory, a bit in the Windows directory, a bit in System32, a bit here and a bit there). In the end, this makes it impossible to cleanly backup or remove something which results in the famous "Windows rot" (i.e. you have to reinstall every few months).
Anyway. If you really don't want to use user.home (and I see no reason not to), use code like this from Apache commons-lang to figure out if you're running on Windows. If this yields true, pop up a directory selection dialog where the user can specify where they want to save their data.
Save this information in Preferences and use this path the next time when your app is started. This way, users can specify where they want their data and you only have to leave one bit of information in the prefs.
For an application "foo" I'd create a directory named ".foo" inside user.home. For Windows it will look slightly strange, but almost noone ever looks in that directory (and it's filled with obscure directories anyway) and on Linux/Solaris/... it will result in a hidden directory that doesn't clutter the users home directory visually.
dynamically read (from your code) the value of APPDATA environment variable, and store your config files in %APPDATA%\\.myapp\config
==> value is platform dependent, do not use any hard-coded paths, always read the env. var.
The problem is not Wiindows but the standard java setup.
Long Discussion
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4787931>Here
I would advise picking this up on a '-D MYLOC=%USERPROFILE%' property on the command line.
Note that you will only get a "USERPROFILE" if the user did a desktop login, this does not get set if the user logged in remotly with citrix or similar or via ssh, also, coprporate desktops mess around with this setting and may set it to something unusable.