What is the best way to find the users home directory in Java

Question

The difficulty is that it should be cross platform  Windows 2000  XP  Vista  OSX  Linux  other unix variants  I am looking for a snippet of code that can accomplish this for all platforms  and a way to detect the platform   Now  you should be aware of bug 4787931 that user home does not work correctly  so please do not provide me of textbook answers  I can find these myself in the manuals

User · Answer

Actually with Java 8 the right way is to use:

System.getProperty("user.home");

The bug JDK-6519127 has been fixed and the "Incompatibilities between JDK 8 and JDK 7" section of the release notes states:

Area: Core Libs / java.lang

Synopsis

The steps used to determine the user's home directory on Windows have changed to follow the Microsoft recommended approach. This change might be observable on older editions of Windows or where registry settings or environment variables are set to other directories. Nature of Incompatibility
behavioral RFE

6519127

Despite the question being old I leave this for future reference.

User · Answer

As I was searching for Scala version  all I could find was McDowell s JNA code above   I include my Scala port here  as there currently isn t anywhere more appropriate   import com sun jna platform win32   object jna       def getHome  java io File             if   com sun jna Platform isWindows                  new java io File System getProperty  user home                      else               val pszPath  Array Char    new Array Char  WinDef MAX PATH              new java io File Shell32 INSTANCE SHGetSpecialFolderPath null  pszPath  ShlObj CSIDL MYDOCUMENTS  false  match                   case true   gt  new String pszPath takeWhile c   gt  c      0                    case        gt  System getProperty  user home                                      As with the Java version  you will need to add Java Native Access  including both jar files  to your referenced libraries   It s nice to see that JNA now makes this much easier than when the original code was posted

User · Answer

If you want something that works well on windows there is a package called WinFoldersJava which wraps the native call to get the  special  directories on Windows   We use it frequently and it works well

User · Answer

System getProperty  user home      See the JavaDoc

User · Answer

Alternative would be to use Apache CommonsIO FileUtils getUserDirectory   instead of System getProperty  user home    It will get you the same result and there is no chance to introduce a typo when specifying system property   There is a big chance you already have Apache CommonsIO library in your project  Don t introduce it if you plan to use it only for getting user home directory

User · Answer

The bug you reference  bug 4787391  has been fixed in Java 8  Even if you are using an older version of Java  the System getProperty  user home   approach is probably still the best  The user home approach seems to work in a very large number of cases  A 100  bulletproof solution on Windows is hard  because Windows has a shifting concept of what the home directory means  If user home isn t good enough for you I would suggest choosing a definition of home directory for windows and using it  getting the appropriate environment variable with System getenv String

User · Answer

The concept of a HOME directory seems to be a bit vague when it comes to Windows  If the environment variables  HOMEDRIVE HOMEPATH USERPROFILE  aren t enough  you may have to resort to using native functions via JNI or JNA  SHGetFolderPath allows you to retrieve special folders  like My Documents  CSIDL  095 PERSONAL  or Local Settings Application Data  CSIDL  095 LOCAL  095 APPDATA    Sample JNA code   public class PrintAppDataDir        public static void main String   args            if  com sun jna Platform isWindows                  HWND hwndOwner   null              int nFolder   Shell32 CSIDL LOCAL APPDATA              HANDLE hToken   null              int dwFlags   Shell32 SHGFP TYPE CURRENT              char   pszPath   new char Shell32 MAX PATH               int hResult   Shell32 INSTANCE SHGetFolderPath hwndOwner  nFolder                      hToken  dwFlags  pszPath               if  Shell32 S OK    hResult                    String path   new String pszPath                   int len   path indexOf   0                    path   path substring 0  len                   System out println path                 else                   System err println  Error      hResult                                      private static Map lt String  Object gt  OPTIONS   new HashMap lt String  Object gt         static           OPTIONS put Library OPTION TYPE MAPPER  W32APITypeMapper UNICODE           OPTIONS put Library OPTION FUNCTION MAPPER                  W32APIFunctionMapper UNICODE              static class HANDLE extends PointerType implements NativeMapped              static class HWND extends HANDLE              static interface Shell32 extends Library            public static final int MAX PATH   260          public static final int CSIDL LOCAL APPDATA   0x001c          public static final int SHGFP TYPE CURRENT   0          public static final int SHGFP TYPE DEFAULT   1          public static final int S OK   0           static Shell32 INSTANCE    Shell32  Native loadLibrary  shell32                   Shell32 class  OPTIONS                           see http   msdn microsoft com en-us library bb762181 VS 85  aspx                        HRESULT SHGetFolderPath  HWND hwndOwner  int nFolder  HANDLE hToken             DWORD dwFlags  LPTSTR pszPath                       public int SHGetFolderPath HWND hwndOwner  int nFolder  HANDLE hToken                  int dwFlags  char   pszPath

User · Answer

I would use the algorithm detailed in the bug report using System getenv String   and fallback to using the user dir property if none of the environment variables indicated a valid existing directory   This should work cross-platform   I think  under Windows  what you are really after is the user s notional  documents  directory

User · Answer

Others have answered the question before me but a useful program to print out all available properties is    for  Map Entry lt     gt  e   System getProperties   entrySet          System out println String format   s    s   e getKey    e getValue

[java] What is the best way to find the users home directory in Java?

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