Ottieni un ID file univoco in Windows con Java?

Question

Sto cercando un modo per ottenere un ID unico file in un'applicazione Java, e sono imbattuto in questo:

Unique file identifier in windows

Ora, ho provato la risposta fornita da Ashley Henderson se stesso (quello che ha chiesto la domanda), e che ha funzionato bene in C#. Ma ho bisogno di farlo in Java, per far funzionare l'app su tutte le piattaforme.

Esiste un modo per eseguire il porting su Java o ottenere lo stesso ID in un altro modo?

EDIT:

ho quasi ottenuto lavorando ora, utilizzando la soluzione eee, solo ho bisogno di essere in una biblioteca, e quando compilo come una biblioteca ottengo un errore, anche se tutto è lavorando bene in un'applicazione di test con tutto incluso. Ma con una libreria separata che si tenta di importare (nessun errore del compilatore) ottengo questo errore di runtime:

debug: 
Exception in thread "main" java.lang.NoClassDefFoundError: com/sun/jna/Structure 
    at java.lang.ClassLoader.defineClass1(Native Method) 
    at java.lang.ClassLoader.defineClass(ClassLoader.java:791) 
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) 
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:449) 
    at java.net.URLClassLoader.access$100(URLClassLoader.java:71) 
    at java.net.URLClassLoader$1.run(URLClassLoader.java:361) 
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354) 
    at java.lang.ClassLoader.loadClass(ClassLoader.java:423) 
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) 
    at java.lang.ClassLoader.loadClass(ClassLoader.java:356) 
    at winfileid.FileId.getFileId(FileId.java:37) 
    at testfileid.TestFileId.main(TestFileId.java:19) 
Caused by: java.lang.ClassNotFoundException: com.sun.jna.Structure 
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366) 
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354) 
    at java.lang.ClassLoader.loadClass(ClassLoader.java:423) 
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) 
    at java.lang.ClassLoader.loadClass(ClassLoader.java:356) 
    ... 14 more 
Java Result: 1 
BUILD SUCCESSFUL (total time: 0 seconds) 

Ho incluso il jna.jar e platform.jar nella libreria quando ho compilato esso ... Per favore ricorda che sono molto nuovo in Java, ma cosa sto sbagliando?

Answer 1

Utilizzando JNA versione 3.3.0: caso

Kernel32.INSTANCE.GetFileInformationByHandle Test: uscita

package win.test; 

import com.sun.jna.platform.win32.Kernel32; 
import com.sun.jna.platform.win32.WinBase; 
import com.sun.jna.platform.win32.WinBase.FILETIME; 
import com.sun.jna.platform.win32.WinNT.HANDLE; 

import win.test.Kernel32.BY_HANDLE_FILE_INFORMATION; 


public class FileTest { 

    /** 
    * @param args 
    */ 
    public static void main(String[] args) { 
     //http://msdn.microsoft.com/en-us/library/windows/desktop/aa363858%28v=vs.85%29.aspx 
     final int FILE_SHARE_READ = (0x00000001); 
     //final int FILE_SHARE_WRITE = (0x00000002); 
     //final int FILE_SHARE_DELETE = (0x00000004); 
     final int OPEN_EXISTING = (3); 
     final int GENERIC_READ = (0x80000000); 
     //final int GENERIC_WRITE = (0x40000000); 
     //final int FILE_FLAG_NO_BUFFERING = (0x20000000); 
     //final int FILE_FLAG_WRITE_THROUGH = (0x80000000); 
     //final int FILE_READ_ATTRIBUTES = (0x0080); 
     //final int FILE_WRITE_ATTRIBUTES = (0x0100); 
     //final int ERROR_INSUFFICIENT_BUFFER = (122); 
     final int FILE_ATTRIBUTE_ARCHIVE = (0x20); 

     WinBase.SECURITY_ATTRIBUTES attr = null; 
     BY_HANDLE_FILE_INFORMATION lpFileInformation = new BY_HANDLE_FILE_INFORMATION(); 
     HANDLE hFile = null; 

     hFile = Kernel32.INSTANCE.CreateFile(args[0], GENERIC_READ, FILE_SHARE_READ, attr, OPEN_EXISTING, FILE_ATTRIBUTE_ARCHIVE, null); 

     System.out.println("CreateFile last error:" + Kernel32.INSTANCE.GetLastError()); 

     //if (hFile. != -1) 
     { 

      win.test.Kernel32.INSTANCE.GetFileInformationByHandle(hFile, lpFileInformation); 

      System.out.println("CREATION TIME: " + FILETIME.filetimeToDate(lpFileInformation.ftCreationTime.dwHighDateTime, lpFileInformation.ftCreationTime.dwLowDateTime)); 

      System.out.println("VOLUME SERIAL NO.: " + Integer.toHexString(lpFileInformation.dwVolumeSerialNumber.intValue())); 

      System.out.println("FILE INDEX HIGH: " + lpFileInformation.nFileIndexHigh); 
      System.out.println("FILE INDEX LOW: " + lpFileInformation.nFileIndexLow); 


      System.out.println("GetFileInformationByHandle last error:" + Kernel32.INSTANCE.GetLastError()); 
     } 

     Kernel32.INSTANCE.CloseHandle(hFile); 

     System.out.println("CloseHandle last error:" + Kernel32.INSTANCE.GetLastError()); 

    } 

} 

Esempio:

CreateFile last error:0 
CREATION TIME: Tue Nov 29 22:24:04 SGT 2011 
VOLUME SERIAL NO.: 900c0655 
FILE INDEX HIGH: 1769472 
FILE INDEX LOW: 286306 
GetFileInformationByHandle last error:0 
CloseHandle last error:0 

Kernel32 JNA classe esempio:

package win.test; 

import java.util.HashMap; 
import java.util.Map; 

import com.sun.jna.Library; 
import com.sun.jna.Native; 
import com.sun.jna.Pointer; 
import com.sun.jna.Structure; 
import com.sun.jna.WString; 
import com.sun.jna.platform.win32.WinBase.FILETIME; 
import com.sun.jna.platform.win32.WinDef.DWORD; 
import com.sun.jna.platform.win32.WinNT.HANDLE; 
import com.sun.jna.win32.StdCallLibrary; 
import com.sun.jna.win32.W32APIFunctionMapper; 
import com.sun.jna.win32.W32APITypeMapper; 

public interface Kernel32 extends StdCallLibrary { 
    final static Map<String, Object> WIN32API_OPTIONS = new HashMap<String, Object>() { 
     private static final long serialVersionUID = 1L; 
     { 
      put(Library.OPTION_FUNCTION_MAPPER, W32APIFunctionMapper.UNICODE); 
      put(Library.OPTION_TYPE_MAPPER, W32APITypeMapper.UNICODE); 
     } 
    }; 

    public Kernel32 INSTANCE = (Kernel32) Native.loadLibrary("Kernel32", Kernel32.class, WIN32API_OPTIONS); 

    public int GetLastError(); 

    /** 
    typedef struct _BY_HANDLE_FILE_INFORMATION { 
      DWORD dwFileAttributes; 
      FILETIME ftCreationTime; 
      FILETIME ftLastAccessTime; 
      FILETIME ftLastWriteTime; 
      DWORD dwVolumeSerialNumber; 
      DWORD nFileSizeHigh; 
      DWORD nFileSizeLow; 
      DWORD nNumberOfLinks; 
      DWORD nFileIndexHigh; 
      DWORD nFileIndexLow; 
     } BY_HANDLE_FILE_INFORMATION, *PBY_HANDLE_FILE_INFORMATION; 
    */ 

    public class BY_HANDLE_FILE_INFORMATION extends Structure { 
     public DWORD dwFileAttributes; 
     public FILETIME ftCreationTime; 
     public FILETIME ftLastAccessTime; 
     public FILETIME ftLastWriteTime; 
     public DWORD dwVolumeSerialNumber; 
     public DWORD nFileSizeHigh; 
     public DWORD nFileSizeLow; 
     public DWORD nNumberOfLinks; 
     public DWORD nFileIndexHigh; 
     public DWORD nFileIndexLow; 
     public static class ByReference extends BY_HANDLE_FILE_INFORMATION implements Structure.ByReference { 

     }; 
     public static class ByValue extends BY_HANDLE_FILE_INFORMATION implements Structure.ByValue { 

     };   
    }; 

    /** 
    BOOL WINAPI GetFileInformationByHandle(
       __in HANDLE hFile, 
       __out LPBY_HANDLE_FILE_INFORMATION lpFileInformation 
      ); 
    */ 
    boolean GetFileInformationByHandle(
       HANDLE hFile, 
       BY_HANDLE_FILE_INFORMATION lpFileInformation 
      ); 
} 

Answer 2

Non è possibile utilizzare il percorso del file come ID univoco?!

percorso completo del file è abbastanza unico nel suo genere ...

Answer 3

In Java si avrebbe bisogno JNI, compilazione nativa C, sia per Windows (utilizzando il codice C#), e per Unix/Linux (usando l'inode di un file). Onestamente non penso che questo sia molto sicuro.