src/jdk.jpackage/share/classes/jdk/jpackage/internal/DeployParams.java

*** 110,128 ****
          }
          resources.add(new RelativeFileSet(
                  baseDir, new LinkedHashSet<>(expandFileset(file))));
      }
  
!     void setClasspath() {
!         String classpath = "";
          for (RelativeFileSet resource : resources) {
               for (String file : resource.getIncludedFiles()) {
                   if (file.endsWith(".jar")) {
                       classpath += file + File.pathSeparator;
                   }
               }
          }
          addBundleArgument(
                  StandardBundlerParam.CLASSPATH.getID(), classpath);
      }
  
      static void validateName(String s, boolean forApp)
--- 110,136 ----
          }
          resources.add(new RelativeFileSet(
                  baseDir, new LinkedHashSet<>(expandFileset(file))));
      }
  
!     void setClasspath(String mainJarPath) {
!         String classpath;
!         // we want main jar first on the classpath
!         if (mainJarPath != null) {
!             classpath = mainJarPath + File.pathSeparator;
!         } else {
!             classpath = "";
!         }
          for (RelativeFileSet resource : resources) {
               for (String file : resource.getIncludedFiles()) {
                   if (file.endsWith(".jar")) {
+                      if (!file.equals(mainJarPath)) {
                           classpath += file + File.pathSeparator;
                       }
                   }
               }
+         }
          addBundleArgument(
                  StandardBundlerParam.CLASSPATH.getID(), classpath);
      }
  
      static void validateName(String s, boolean forApp)