code: private boolean checkFilesExists(String[] requiredFiles, File childResource) {
  
          File setupFile = null;
          boolean hasMissingSetupFiles = false;
  
          for (int j = 0; j < requiredFiles.length; j++) {
              setupFile = new File(childResource.getPath() + File.separatorChar + requiredFiles[j]);
  
              if (!setupFile.exists() || !setupFile.isFile() || !setupFile.canRead()) {
                  hasMissingSetupFiles = true;
                  System.err.println(
                      "[" + getClass().getName() + "] missing or unreadable database setup file: " + setupFile.getPath());
                  break;
              }
  
              if (!hasMissingSetupFiles) {
                  return true;
              }
          }
          return false;
      }
docs: Checks if the necessary files for the configuration are existent or not.<p>
  
  @param requiredFiles the required files
  @param childResource the folder to check
  
  @return true if the files are existent