code: public static void deleteDirectoryQuickly(File dir) throws IOException {
  
          if (!dir.exists()) {
              return;
          }
          final File to = new File(dir.getAbsolutePath() + System.currentTimeMillis());
          dir.renameTo(to);
          if (!dir.exists()) {
              // rebuild
              dir.mkdirs();
          }
  
          // try to run "rm -r" to remove the whole directory
          if (to.exists()) {
              String deleteCmd = "rm -r " + to;
              Runtime runtime = Runtime.getRuntime();
              try {
                  Process process = runtime.exec(deleteCmd);
                  process.waitFor();
              } catch (IOException e) {
  
              } catch (InterruptedException e) {
                  e.printStackTrace();
              }
          }
          if (!to.exists()) {
              return;
          }
          deleteDirectoryRecursively(to);
          if (to.exists()) {
              to.delete();
          }
      }
docs: Try to delete directory in a fast way.