private void checkLibraries() {
   if (line.hasOption(LIBRARIES)) {
     Set<String> merged = JavadocOfflineSearch.listLibraries();
     List<String> configList = JavadocOfflineSearch.getConigLIbraries();
     List<String> cacheList = JavadocOfflineSearch.getCacheLIbraries();
     if (merged.isEmpty()) {
       System.out.println("No library found. You did not run -index yet");
     } else {
       // first verify files
       System.out.println("    Files sanity:");
       for (String library : merged) {
         verify(library);
       }
       System.out.println(
           "* - prefixed library is default (see config file of "
               + LibraryManager.defaultLibDefName
               + ")");
       // second only invalid libraries
       System.out.println("    Possibly corrupted libraries:");
       for (String library : merged) {
         if (configList.contains(library) && cacheList.contains(library)) {
           // prefixLIbrary(library);
           // System.out.println(library);
         } else if (!configList.contains(library) && cacheList.contains(library)) {
           prefixLIbrary(library);
           System.out.println("WARNING only in cache folder - " + library);
         } else if (configList.contains(library) && !cacheList.contains(library)) {
           prefixLIbrary(library);
           System.out.println("WARNING only in config folder - " + library);
         } else {
           prefixLIbrary(library);
           System.out.println("Error, library from different planet - " + library);
         }
       }
       // last only valid libraries
       System.out.println("    Libraries:");
       for (String library : merged) {
         if (configList.contains(library) && cacheList.contains(library)) {
           prefixLIbrary(library);
           System.out.println(library);
         } else if (!configList.contains(library) && cacheList.contains(library)) {
           // prefixLIbrary(library);
           // System.out.println("WARNING only in cache folder - " + library);
         } else if (configList.contains(library) && !cacheList.contains(library)) {
           // prefixLIbrary(library);
           // System.out.println("WARNING only in config folder - " + library);
         } else {
           // prefixLIbrary(library);
           // System.out.println("Error, library from different planet - " + library);
         }
       }
     }
     System.exit(0);
   }
 }