protected native String canonicalize0(String path) throws IOException

 protected native String canonicalizeWithPrefix0(String canonicalPrefix,
    String pathWithCanonicalPrefix) throws IOException

 public native boolean checkAccess(File f,
    int access)

 public native boolean createDirectory(File f)

 public native boolean createFileExclusively(String path) throws IOException

 protected native boolean delete0(File f)

 public native int getBooleanAttributes(File f)

 protected native String getDriveDirectory(int drive)

 public native long getLastModifiedTime(File f)

 public native long getLength(File f)

 public long getSpace(File f,
    int t) 
{
        if (f.exists()) {
            return getSpace0(f, t);
        }
        return 0;
}

 public native String[] list(File f)

 protected native boolean rename0(File f1,
    File f2)

 public native boolean setLastModifiedTime(File f,
    long time)

 public native boolean setPermission(File f,
    int access,
    boolean enable,
    boolean owneronly)

 public native boolean setReadOnly(File f)