MVStore: use NIO even in Windows when using a file name with drive name.

h2/src/main/org/h2/mvstore/FileStore.java

@@ -14,6 +14,7 @@ import java.nio.channels.OverlappingFileLockException;
 
 import org.h2.mvstore.cache.FilePathCache;
 import org.h2.store.fs.FilePath;
+import org.h2.store.fs.FilePathDisk;
 import org.h2.store.fs.FilePathEncrypt;
 import org.h2.store.fs.FilePathNio;
 
@@ -111,12 +112,14 @@ public class FileStore {
      *            used
      */
     public void open(String fileName, boolean readOnly, char[] encryptionKey) {
-        if (fileName != null && fileName.indexOf(':') < 0) {
+        if (fileName != null) {
+            if (FilePath.get(fileName) instanceof FilePathDisk) {            
                 // NIO is used, unless a different file system is specified
                 // the following line is to ensure the NIO file system is compiled
                 FilePathNio.class.getName();
                 fileName = "nio:" + fileName;
             }
+        }
         this.fileName = fileName;
         FilePath f = FilePath.get(fileName);
         FilePath parent = f.getParent();