modules/fxpackager/src/main/java/com/oracle/tools/packager/JDepHelper.java

*** 66,80 ****
          try (ByteArrayOutputStream baos = new ByteArrayOutputStream();
               PrintWriter writer = new PrintWriter(baos)) {
  
              List<String> arguments = new ArrayList<>();
              arguments.add("-s");
!             //TODO JDK-8148654 - add support for -modulepath.
!             //if (modulePath != null || !modulePath.empty()) {
!             //    arguments.add("-modulepath");
!             //    ...
!             //}
              arguments.addAll(Files);
  
              invokeJdep(arguments.toArray(new String[arguments.size()]), writer);
  
              // output format is multiple lines of "this.jar -> that.module.name"
--- 66,81 ----
          try (ByteArrayOutputStream baos = new ByteArrayOutputStream();
               PrintWriter writer = new PrintWriter(baos)) {
  
              List<String> arguments = new ArrayList<>();
              arguments.add("-s");
! 
!             if (modulePath != null || !modulePath.isEmpty()) {
!                 arguments.add("-modulepath");
!                 arguments.add(ListOfPathToString(modulePath));
!             }
! 
              arguments.addAll(Files);
  
              invokeJdep(arguments.toArray(new String[arguments.size()]), writer);
  
              // output format is multiple lines of "this.jar -> that.module.name"
*** 86,91 ****
--- 87,107 ----
          } catch (IOException ioe) {
              Log.verbose(ioe);
              return new LinkedHashSet();
          }
      }
+ 
+     private static String ListOfPathToString(List<Path> Value) {
+         String result = "";
+ 
+         for (Path path : Value) {
+             if (result.isEmpty()) {
+                 result = path.toString();
+             }
+             else {
+                 result = File.pathSeparator + path.toString();
+             }
+         }
+ 
+         return result;
+     }
  }