void onPreStart(){
  log.info("Remove all dirs under {}",dbDir);
  File dir=new File(dbDir);
  try {
    for (    File file : dir.listFiles()) {
      if (!file.isDirectory()) {
        continue;
      }
      FileUtils.deleteDirectory(file);
      log.info("Delete directory({}) successful",file.getAbsolutePath());
    }
  }
 catch (  IOException ex) {
    log.warn("Could not cleanup db directory {}",dbDir);
    throw new IllegalStateException("Error when cleanup db dir",ex);
  }
}

void onPreStart ( ) { log . info ( "Remove all dirs under {}" , dbDir ) ; File dir = new File ( dbDir ) ; try { for ( File file : dir . listFiles ( ) ) { if ( ! file . isDirectory ( ) ) { continue ; } FileUtils . deleteDirectory ( file ) ; log . info ( "Delete directory({}) successful" , file . getAbsolutePath ( ) ) ; } } catch ( IOException ex ) { log . warn ( "Could not cleanup db directory {}" , dbDir ) ; throw new IllegalStateException ( "Error when cleanup db dir" , ex ) ; } }
remove all db / commitlog files - including system and geostorageos keyspace
