docs: protected void definePackage(File container, String packageName, Manifest manifest) {
          String sectionName = packageName.replace('.', '/') + "/";
  
          String specificationTitle = null;
          String specificationVendor = null;
          String specificationVersion = null;
          String implementationTitle = null;
          String implementationVendor = null;
          String implementationVersion = null;
          String sealedString = null;
          URL sealBase = null;
  
          Attributes sectionAttributes = manifest.getAttributes(sectionName);
          if (sectionAttributes != null) {
              specificationTitle = sectionAttributes.getValue(Name.SPECIFICATION_TITLE);
              specificationVendor = sectionAttributes.getValue(Name.SPECIFICATION_VENDOR);
              specificationVersion = sectionAttributes.getValue(Name.SPECIFICATION_VERSION);
              implementationTitle = sectionAttributes.getValue(Name.IMPLEMENTATION_TITLE);
              implementationVendor = sectionAttributes.getValue(Name.IMPLEMENTATION_VENDOR);
              implementationVersion = sectionAttributes.getValue(Name.IMPLEMENTATION_VERSION);
              sealedString = sectionAttributes.getValue(Name.SEALED);
          }
          Attributes mainAttributes = manifest.getMainAttributes();
          if (mainAttributes != null) {
              if (specificationTitle == null) {
                  specificationTitle = mainAttributes.getValue(Name.SPECIFICATION_TITLE);
              }
              if (specificationVendor == null) {
                  specificationVendor = mainAttributes.getValue(Name.SPECIFICATION_VENDOR);
              }
              if (specificationVersion == null) {
                  specificationVersion = mainAttributes.getValue(Name.SPECIFICATION_VERSION);
              }
              if (implementationTitle == null) {
                  implementationTitle = mainAttributes.getValue(Name.IMPLEMENTATION_TITLE);
              }
              if (implementationVendor == null) {
                  implementationVendor = mainAttributes.getValue(Name.IMPLEMENTATION_VENDOR);
              }
              if (implementationVersion == null) {
                  implementationVersion = mainAttributes.getValue(Name.IMPLEMENTATION_VERSION);
              }
              if (sealedString == null) {
                  sealedString = mainAttributes.getValue(Name.SEALED);
              }
          }
          if (sealedString != null && sealedString.equalsIgnoreCase("true")) {
              try {
                  sealBase = new URL(FileUtils.getFileUtils().toURI(container.getAbsolutePath()));
              } catch (MalformedURLException e) {
                  // ignore
              }
          }
          definePackage(packageName, specificationTitle, specificationVersion, specificationVendor,
                  implementationTitle, implementationVersion, implementationVendor, sealBase);
      }