I am trying to play youtube video using vlcj.
"NativeLibrary.addSearchPath(RuntimeUtil.getLibVlcLibraryName()," C:\\Program Files \\VideoLAN\\VLC");"
So I am trying to load a library using this code.
However, the libvlc.dll and libvlccore.dll files could not be loaded due to an error.
`
java.lang.RuntimeException: Failed to load the native library.
The error was "Unable to load library 'libvlc': Native library (win32-x86-64/libvlc.dll) not found in resource path ([file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/charsets.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/deploy.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/access-bridge-64.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/cldrdata.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/dnsns.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/jaccess.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/jfxrt.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/localedata.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/nashorn.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/sunec.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/sunjce_provider.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/sunmscapi.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/sunpkcs11.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/ext/zipfs.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/javaws.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/jce.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/jfr.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/jfxswt.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/jsse.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/management-agent.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/plugin.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/resources.jar, file:/C:/Program%20Files/Java/jdk1.8.0_181/jre/lib/rt.jar, file:/D:/project/AnimalCrossing/mod/build/classes/main/, file:/D:/project/AnimalCrossing/mod/build/resources/main/, file:/D:/project/AnimalCrossing/mod/libs/slf4j-api-1.7.9.jar, file:/D:/project/AnimalCrossing/mod/libs/vlcj.jar, file:/C:/Users/gustj/.gradle/caches/minecraft/deobfedDeps/compileDummy.jar, file:/C:/Users/gustj/.gradle/caches/minecraft/deobfedDeps/providedDummy.jar, file:/C:/Users/gustj/.gradle/caches/minecraft/net/minecraftforge/forge/1.12.2-14.23.5.2847/snapshot/20171003/forgeSrc-1.12.2-14.23.5.2847.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.google.code.findbugs/jsr305/3.0.1/f7be08ec23c21485b9b5a1cf1654c2ec8c58168d/jsr305-3.0.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.mojang/patchy/1.1/aef610b34a1be37fa851825f12372b78424d8903/patchy-1.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/oshi-project/oshi-core/1.1/9ddf7b048a8d701be231c0f4f95fd986198fd2d8/oshi-core-1.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.java.dev.jna/jna/4.4.0/cb208278274bf12ebdb56c61bd7407e6f774d65a/jna-4.4.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.java.dev.jna/platform/3.4.0/e3f70017be8100d3d6923f50b3d2ee17714e9c13/platform-3.4.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.ibm.icu/icu4j-core-mojang/51.2/63d216a9311cca6be337c1e458e587f99d382b84/icu4j-core-mojang-51.2.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.sf.jopt-simple/jopt-simple/5.0.3/cdd846cfc4e0f7eefafc02c0f5dce32b9303aa2a/jopt-simple-5.0.3.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/io.netty/netty-all/4.1.9.Final/97860965d6a0a6b98e7f569f3f966727b8db75/netty-all-4.1.9.Final.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.google.guava/guava/21.0/3a3d111be1be1b745edfa7d91678a12d7ed38709/guava-21.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.apache.commons/commons-lang3/3.5/6c6c702c89bfff3cd9e80b04d668c5e190d588c6/commons-lang3-3.5.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/commons-io/commons-io/2.5/2852e6e05fbb95076fc091f6d1780f1f8fe35e0f/commons-io-2.5.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/commons-codec/commons-codec/1.10/4b95f4897fa13f2cd904aee711aeafc0c5295cd8/commons-codec-1.10.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.java.jutils/jutils/1.0.0/e12fe1fda814bd348c1579329c86943d2cd3c6a6/jutils-1.0.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.google.code.gson/gson/2.8.0/c4ba5371a29ac9b2ad6129b1d39ea38750043eff/gson-2.8.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.mojang/authlib/1.5.25/9834cdf236c22e84b946bba989e2f94ef5897c3c/authlib-1.5.25.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.mojang/realms/1.10.22/bd0dccebdf3744c75f1ca20063f16e8f7d5e663f/realms-1.10.22.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.apache.commons/commons-compress/1.8.1/a698750c16740fd5b3871425f4cb3bbaa87f529d/commons-compress-1.8.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.apache.httpcomponents/httpclient/4.3.3/18f4247ff4572a074444572cee34647c43e7c9c7/httpclient-4.3.3.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/commons-logging/commons-logging/1.1.3/f6f66e966c70a83ffbdb6f17a0919eaf7c8aca7f/commons-logging-1.1.3.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.apache.httpcomponents/httpcore/4.3.2/31fbbff1ddbf98f3aa7377c94d33b0447c646b6e/httpcore-4.3.2.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/it.unimi.dsi/fastutil/7.1.0/9835253257524c1be7ab50c057aa2d418fb72082/fastutil-7.1.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-api/2.8.1/e801d13612e22cad62a3f4f3fe7fdbe6334a8e72/log4j-api-2.8.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-core/2.8.1/4ac28ff2f1ddf05dae3043a190451e8c46b73c31/log4j-core-2.8.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.mojang/text2speech/1.10.3/48fd510879dff266c3815947de66e3d4809f8668/text2speech-1.10.3.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.minecraft/launchwrapper/1.12/111e7bea9c968cdb3d06ef4632bf7ff0824d0f36/launchwrapper-1.12.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.jline/jline/3.5.1/51800e9d7a13608894a5a28eed0f5c7fa2f300fb/jline-3.5.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.ow2.asm/asm-debug-all/5.2/3354e11e2b34215f06dab629ab88e06aca477c19/asm-debug-all-5.2.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.typesafe.akka/akka-actor_2.11/2.3.3/ed62e9fc709ca0f2ff1a3220daa8b70a2870078e/akka-actor_2.11-2.3.3.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.typesafe/config/1.2.1/f771f71fdae3df231bcd54d5ca2d57f0bf93f467/config-1.2.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang/scala-actors-migration_2.11/1.1.0/dfa8bc42b181d5b9f1a5dd147f8ae308b893eb6f/scala-actors-migration_2.11-1.1.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang/scala-compiler/2.11.1/56ea2e6c025e0821f28d73ca271218b8dd04926a/scala-compiler-2.11.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang.plugins/scala-continuations-library_2.11/1.0.2/e517c53a7e9acd6b1668c5a35eccbaa3bab9aac/scala-continuations-library_2.11-1.0.2.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang.plugins/scala-continuations-plugin_2.11.1/1.0.2/f361a3283452c57fa30c1ee69448995de23c60f7/scala-continuations-plugin_2.11.1-1.0.2.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang/scala-library/2.11.1/e11da23da3eabab9f4777b9220e60d44c1aab6a/scala-library-2.11.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang.modules/scala-parser-combinators_2.11/1.0.1/f05d7345bf5a58924f2837c6c1f4d73a938e1ff0/scala-parser-combinators_2.11-1.0.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang/scala-reflect/2.11.1/6580347e61cc7f8e802941e7fde40fa83b8badeb/scala-reflect-2.11.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang.modules/scala-swing_2.11/1.0.1/b1cdd92bd47b1e1837139c1c53020e86bb9112ae/scala-swing_2.11-1.0.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang.modules/scala-xml_2.11/1.0.2/820fbca7e524b530fdadc594c39d49a21ea0337e/scala-xml_2.11-1.0.2.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/lzma/lzma/0.0.1/521616dc7487b42bef0e803bd2fa3faf668101d7/lzma-0.0.1.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.sf.trove4j/trove4j/3.0.3/42ccaf4761f0dfdfa805c9e340d99a755907e2dd/trove4j-3.0.3.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.apache.maven/maven-artifact/3.5.3/7dc72b6d6d8a6dced3d294ed54c2cc3515ade9f4/maven-artifact-3.5.3.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.paulscode/codecjorbis/20101023/c73b5636faf089d9f00e8732a829577de25237ee/codecjorbis-20101023.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.paulscode/codecwav/20101023/12f031cfe88fef5c1dd36c563c0a3a69bd7261da/codecwav-20101023.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.paulscode/libraryjavasound/20101123/5c5e304366f75f9eaa2e8cca546a1fb6109348b3/libraryjavasound-20101123.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.paulscode/librarylwjglopenal/20100824/73e80d0794c39665aec3f62eee88ca91676674ef/librarylwjglopenal-20100824.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/com.paulscode/soundsystem/20120107/419c05fe9be71f792b2d76cfc9b67f1ed0fec7f6/soundsystem-20120107.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.java.jinput/jinput/2.0.5/39c7796b469a600f72380316f6b1f11db6c2c7c4/jinput-2.0.5.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.lwjgl.lwjgl/lwjgl/2.9.4-nightly-20150209/697517568c68e78ae0b4544145af031c81082dfe/lwjgl-2.9.4-nightly-20150209.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.lwjgl.lwjgl/lwjgl_util/2.9.4-nightly-20150209/d51a7c040a721d13efdfbd34f8b257b2df882ad0/lwjgl_util-2.9.4-nightly-20150209.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/java3d/vecmath/1.5.2/79846ba34cbd89e2422d74d53752f993dcc2ccaf/vecmath-1.5.2.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/ca.weblite/java-objc-bridge/1.0.0/6ef160c3133a78de015830860197602ca1c855d3/java-objc-bridge-1.0.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.scala-lang/scala-actors/2.11.0/8ccfb6541de179bb1c4d45cf414acee069b7f78b/scala-actors-2.11.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.codehaus.plexus/plexus-utils/3.1.0/60eecb6f15abdb1c653ad80abaac6fe188b3feaa/plexus-utils-3.1.0.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.java.jinput/jinput-platform/2.0.5/7ff832a6eb9ab6a767f1ade2b548092d0fa64795/jinput-platform-2.0.5-natives-linux.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.java.jinput/jinput-platform/2.0.5/385ee093e01f587f30ee1c8a2ee7d408fd732e16/jinput-platform-2.0.5-natives-windows.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/net.java.jinput/jinput-platform/2.0.5/53f9c919f34d2ca9de8c51fc4e1e8282029a9232/jinput-platform-2.0.5-natives-osx.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.lwjgl.lwjgl/lwjgl-platform/2.9.4-nightly-20150209/b84d5102b9dbfabfeb5e43c7e2828d98a7fc80e0/lwjgl-platform-2.9.4-nightly-20150209-natives-windows.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.lwjgl.lwjgl/lwjgl-platform/2.9.4-nightly-20150209/931074f46c795d2f7b30ed6395df5715cfd7675b/lwjgl-platform-2.9.4-nightly-20150209-natives-linux.jar, file:/C:/Users/gustj/.gradle/caches/modules-2/files-2.1/org.lwjgl.lwjgl/lwjgl-platform/2.9.4-nightly-20150209/bcab850f8f487c3f4c4dbabde778bb82bd1a40ed/lwjgl-platform-2.9.4-nightly-20150209-natives-osx.jar, file:/C:/Users/gustj/.gradle/caches/minecraft/net/minecraftforge/forge/1.12.2-14.23.5.2847/start/, file:/C:/Program%20Files/JetBrains/IntelliJ%20IDEA%20Community%20Edition%202019.3.1/lib/idea_rt.jar, file:/C:/Users/gustj/.IdeaIC2019.3/system/groovyHotSwap/gragent.jar, file:/C:/Users/gustj/.IdeaIC2019.3/system/captureAgent/debugger-agent.jar, asmgen:/])".
The required native libraries are named "libvlc.dll" and "libvlccore.dll".
In the text below <libvlc-path> represents the name of the directory containing "libvlc.dll" and "libvlccore.dll"...
There are a number of different ways to specify where to find the native libraries:
1. Include NativeLibrary.addSearchPath("libvlc", "<libvlc-path>"); at the start of your application code.
2. Include System.setProperty("jna.library.path", "<libvlc-path>"); at the start of your application code.
3. Specify -Djna.library.path=<libvlc-path> on the command-line when starting your application.
4. Add <libvlc-path> to the system search path (and reboot).
If this still does not work, then it may be necessary to explicitly add the native library directory to the operating
system configuration - e.g. on Linux this might mean setting the LD_LIBRARY_PATH environment variable, or adding
configuration to the "/etc/ld.so.conf" file or the "/etc/ld.so.conf.d" directory. Of these options, setting
LD_LIBRARY_PATH is the only one that would not require root privileges.
Finally, it is not possible to mix CPU architectures - it is not possible for a 64-bit Java Virtual Machine to load
32-bit native libraries.
More information may be available in the log.
`
I installed 64-bit 1.8.0_181 jvm, jre, and vlc is also 64-bit installed in the "C:\Program Files\VideoLAN\VLC" folder. and I use vlcj 3.11.0, jna 4.4.0, jna-platform 3.4.0 version. how can I solve it?
I am trying to set up On Demand Server in my local machine and when ever I am deploying the application on tomcat server I am getting below error message on browser. I have updated the PATH variable also.
root cause
java.lang.UnsatisfiedLinkError: ars3wapi32 (Not found in java.library.path)
java.lang.ClassLoader.loadLibraryWithPath(ClassLoader.java:1007)
java.lang.ClassLoader.loadLibraryWithClassLoader(ClassLoader.java:971)
java.lang.System.loadLibrary(System.java:470)
com.ibm.edms.od.ArsWWWInterface.<clinit>(ArsWWWInterface.java:15)
java.lang.J9VMInternals.initializeImpl(Native Method)
java.lang.J9VMInternals.initialize(J9VMInternals.java:200)
com.ibm.edms.od.ODServer.<init>(ODServer.java:45)
com.ibm.edms.od.ODServer.<init>(ODServer.java:61)
com.uklife.web.ondemand.utils.DownloadUtils.getAFPDocumentFromOnDemand(DownloadUtils.java:80)
com.uklife.web.ondemand.utils.Utils.getDocument(Utils.java:288)
com.uklife.web.ondemand.servlet.OnDemandDocAccess.doGet(OnDemandDocAccess.java:81)
javax.servlet.http.HttpServlet.s`enter code here`ervice(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722
)
Here is a guide the solution (for Windows and OnDemand V9.5).
First of all, you need to install ODWEK on the machine where you want to run your java app. Please install in the default folder, this whole thing is tricky enough as it is...
Set the environment variable "PATH" in Windows, add "C:\Program Files\IBM\OnDemand\V9.5\bin"
Set CLASSPATH in your development environment - point out the ODApi.jar file and ALSO point "Native library..." to the \bin folder above. (You can also call the program and setting the CLASSPATH in the call as a parameter: -Djava.library.path="C:\Program Files\IBM\OnDemand\V9.5\www\api\ODapi.jar"
Copy the file ars3wapi64.dll from C:\Program Files\IBM\V9.5\www to C:\Program Files\IBM\OnDemand\V9.5\bin
Ensure that all of these files are in the bin-catalog above:
**ars3wapi64.dll**
icudt53.dll
icuin53.dll
icuio53.dll
icule53.dll
iculx53.dll
icuuc53.dll
arsgsk64.dll
If you are getting the error "java.lang.UnsatisfiedLinkError: ars3wapi32 (Not found in java.library.path)" one of the above is most likely incorrect.
OR you could be using different versions of ODWEK and OnDemand.
More on how to set CLASSPATH in Eclipse: How to set the java.library.path from Eclipse
In my app I am saving temporary files to my app cache folder. I am getting the name of the cache directory via this method:
context.getCacheDir();
It returns me such path: /data/user/0/my.app.packagename
But later when I am trying to get name of parent directory of my cache file via this method - file.getParent(); I am getting absolutely different path to cache directory, in my case this: /data/data/my.app-packagename
So I am just wondering why this is happening, why getParent() doesn't return the same path as context.getCacheDir()?
The behaviour is correct, technically its the same.
If you connect to your android device via adb shell and go into /data/user/ and run the 'll' command you will see that the folder 0 is just a symbolic link to /data/data/.
root#android:/data/user # ll
lrwxrwxrwx root root 1970-01-01 01:00 0 -> /data/data/
If you dont know what that means, read up on symbolic links.
So there is no issue and you can trust android that they are the same.
This behavior confused me a lot today.
Here are my 50 Cent to bring light into this:
I've started an Emulator with Android 8.1
I've connected my Android 9 Device via USB
After that I've started Android-Studio and opend the Device File Explorer.
Now strange things happend:
On Android 8.1 you see the structure /data/user/0/com.myApp/
on Android 9 there is no directory /data/user (and no symbolic link visible via android-studio)
BUT, internally the path seems to be the same (even if there is no symbolic Link visible in android studio).
I use RNFetchBlob (React native package to read files), and if I output the Result from RNFetchBlob.fs.dirs.CacheDir the result was /data/user/0/.... even if on Android 9 this Directory not exist.
But I'd gave it a try and output all files that will be found at this Directory with the following Command :
RNFetchBlob.fs.ls(RNFetchBlob.fs.dirs.CacheDir)
.then((files) => {
console.log("output-files",files);
})
...and found that this output all the files I've cached before.
If anybody knows some documentation why this behavior exist up from Android 9, please comment and point us to this.
Windows Scenario :-
I have a small piece of code which gets me the location of a specific folder in the directory. The code is as given below:
browserPath = this.EnginePath + "\\Chrome_Selenium\\" + "chromedriver.exe";
This gets me the exact path : D:\Engine\Test
I am trying to use the same logic to get the path in linux machine.
The path where the Engine and Chrome Driver is stored in my linux machine (VM) is
/root/Engine/Chrome_Selenium
Now the linux part :-
I am using the following piece of code to get that
browserPath = this.EnginePath + "/Chrome_Selenium/" + "chromedriver";
The path this piece of code fetches is
/root/Engine/.\Chrome_Selenium\chromedriver
Can you please help me understand why the "/.\" is appearing in the path?
I am guessing the reason why ./ is added is because in linux in order to execute a script in the present working directory you need to address it this way: ./script instead of script. Somehow it is attached even in cases where it is not needed (execution in other folder)
As for the main part as Alfe mentioned it does not make any different at the first place.
How can I write system preferences with Java, using Preferences.systemRoot()?
I tried with:
Preferences preferences = Preferences.systemRoot();
preferences.put("/myapplication/databasepath", pathToDatabase);
But I got this error message:
2010-maj-29 19:02:50 java.util.prefs.WindowsPreferences openKey
VARNING: Could not open windows registry node Software\JavaSoft\Prefs at root 0x80000002. Windows RegOpenKey(...) returned error code 5.
Exception in thread "AWT-EventQueue-0" java.lang.SecurityException: Could not open windows registry node Software\JavaSoft\Prefs at root 0x80000002: Access denied
at java.util.prefs.WindowsPreferences.openKey(Unknown Source)
at java.util.prefs.WindowsPreferences.openKey(Unknown Source)
at java.util.prefs.WindowsPreferences.openKey(Unknown Source)
at java.util.prefs.WindowsPreferences.putSpi(Unknown Source)
at java.util.prefs.AbstractPreferences.put(Unknown Source)
at org.example.install.Setup$2.actionPerformed(Setup.java:43)
I would like to do this, because I want to install an embedded JavaDB database, and let multiple users on the computer to use the same database with the application.
How to solve this? Can I invoke UAC and do this as Administrator from Java? And if I log in as Administrator when writing, can I read the values with my Java application if I'm logged in as a User?
You cannot write to any arbitrary registry location from java preferences - all preferences are stored under a subkey Software\Javasoft\Prefs. With user preferences mapping to the HKEY_CURRENT_USER hive, and system mapping to the HKEY_LOCAL_MACHINE hive.
To write to the registry, you could use the windows "REG" command line tool. This page details other ways of modifying the registry. including use of .reg files.
I had the same need - to write to the registry from java - I solved it by writing a small .NET command line utility to do it.
The Sun Windows JDK does ship with generic code to write to arbitrary portions of the registry (WindowsPreferences), but it's not public. This article describes how to access this class using reflection.
You can't edit Preferences.systemRoot() if User Account Control is turned on. Seems like Microsoft went and broke it. There is a workaround here, but it's not straightforward.
So I had this same issue, so I opened an issue with Oracle:
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7043176
I was able to work around it myself, by writing a custom implementation of AbstractPreferences and a corresponding PreferencesFactory. What I did was on Windows have the system preferences write to the application data directory defined in the registry by:
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders\Common AppData
I used Runtime.getRuntime().exec("reg query \""+key+ "\" /v \""+value+"\"") to get that (works even with UAC turned on).
That evaluates to "C:\ProgramData" on Windows 7 and "C:\Documents and Settings\All Users\Application Data" on XP. I added a subdirectory called "JavaPreferences" and wrote an implementation that uses a properties file as the backend.
As a side note, I had a similar issue with system preferences on Linux because the installer for the JRE was not run by root so I didn't have access to "/etc/.java". A ended up picking another custom directory and granting permissions for that.