Program: 7525
Project: 7525
Buggy source:
@Override public void onEnable(){
  File backupDir=new File("String_Node_Str".concat(FILE_SEPARATOR).concat("String_Node_Str"));
  if (!backupDir.exists())   backupDir.mkdirs();
  backupDir=new File("String_Node_Str");
  if (!backupDir.exists())   backupDir.mkdirs();
  backupDir=new File("String_Node_Str".concat(FILE_SEPARATOR).concat("String_Node_Str"));
  if (!backupDir.exists())   backupDir.mkdirs();
  @SuppressWarnings("String_Node_Str") int saveTaskID=this.getServer().getScheduler().scheduleSyncRepeatingTask(this,new AutoSaveThread(this),120 * 21L,1100 * 21L);
  @SuppressWarnings("String_Node_Str") int backupTaskID=this.getServer().getScheduler().scheduleSyncRepeatingTask(this,new BackupTask(this.getServer()),1800 * 21L,1800 * 21L);
  System.out.println("String_Node_Str");
  setupDatabase();
  registerEvents();
  getCommand("String_Node_Str").setExecutor(new RestoreInventoryCommand(this));
  getCommand("String_Node_Str").setExecutor(new GetDirection());
  getCommand("String_Node_Str").setExecutor(new MakeCartTunnelCommand());
  getCommand("String_Node_Str").setExecutor(new GiveTrackCommand());
  getCommand("String_Node_Str").setExecutor(new RegenChunkCommand(this));
  getCommand("String_Node_Str").setExecutor(new WallChunkCommand());
  getCommand("String_Node_Str").setExecutor(new StoreCommand(shopFunctions));
  getCommand("String_Node_Str").setExecutor(new BuyCommand(bankFunctions,shopFunctions));
  getCommand("String_Node_Str").setExecutor(new ChallangeCommand());
  getCommand("String_Node_Str").setExecutor(new DieCommand(this));
  getCommand("String_Node_Str").setExecutor(new BankCommand(this));
  getCommand("String_Node_Str").setExecutor(new SetCompassCommand());
  getCommand("String_Node_Str").setExecutor(new SetSpawnLocationCommand());
  getCommand("String_Node_Str").setExecutor(new KillFarmAnimalsCommand());
  getCommand("String_Node_Str").setExecutor(new KillHostileMobsCommand());
  getCommand("String_Node_Str").setExecutor(new SpawnMobCommand());
  getCommand("String_Node_Str").setExecutor(new WhoCommand());
  getCommand("String_Node_Str").setExecutor(new TeleportCommand());
  getCommand("String_Node_Str").setExecutor(new SetRankCommand(rankFunctions));
  getCommand("String_Node_Str").setExecutor(new ChestHelpCommand());
  getCommand("String_Node_Str").setExecutor(new GetChestCountCommand(chestFunctions));
  getCommand("String_Node_Str").setExecutor(new UnlockChestCommand(chestFunctions));
  PluginDescriptionFile pdfFile=this.getDescription();
  deathevents.put("String_Node_Str",getConfiguration().getStringList("String_Node_Str",null));
  System.out.println(pdfFile.getName() + "String_Node_Str" + pdfFile.getVersion()+ "String_Node_Str");
  if (!PluginFile.exists()) {
    try {
      new File(maindirectory).mkdir();
      PluginFile.createNewFile();
    }
 catch (    IOException e) {
      e.printStackTrace();
    }
  }
  if (!shopFile.exists()) {
    try {
      new File(maindirectory).mkdir();
      shopFile.createNewFile();
    }
 catch (    IOException e) {
      e.printStackTrace();
    }
  }
}

Fixed version (ground truth):
@Override public void onEnable(){
  File backupDir=new File("String_Node_Str".concat(FILE_SEPARATOR).concat("String_Node_Str"));
  if (!backupDir.exists())   backupDir.mkdirs();
  backupDir=new File("String_Node_Str");
  if (!backupDir.exists())   backupDir.mkdirs();
  backupDir=new File("String_Node_Str".concat(FILE_SEPARATOR).concat("String_Node_Str"));
  if (!backupDir.exists())   backupDir.mkdirs();
  @SuppressWarnings("String_Node_Str") int saveTaskID=this.getServer().getScheduler().scheduleSyncRepeatingTask(this,new AutoSaveThread(this),120 * 21L,1100 * 21L);
  @SuppressWarnings("String_Node_Str") int backupTaskID=this.getServer().getScheduler().scheduleSyncRepeatingTask(this,new BackupTask(this.getServer()),3800 * 21L,3400 * 21L);
  System.out.println("String_Node_Str");
  setupDatabase();
  registerEvents();
  getCommand("String_Node_Str").setExecutor(new RestoreInventoryCommand());
  getCommand("String_Node_Str").setExecutor(new GetDirection());
  getCommand("String_Node_Str").setExecutor(new MakeCartTunnelCommand());
  getCommand("String_Node_Str").setExecutor(new GiveTrackCommand());
  getCommand("String_Node_Str").setExecutor(new RegenChunkCommand(this));
  getCommand("String_Node_Str").setExecutor(new WallChunkCommand());
  getCommand("String_Node_Str").setExecutor(new StoreCommand(shopFunctions));
  getCommand("String_Node_Str").setExecutor(new BuyCommand(bankFunctions,shopFunctions));
  getCommand("String_Node_Str").setExecutor(new ChallangeCommand());
  getCommand("String_Node_Str").setExecutor(new DieCommand(this));
  getCommand("String_Node_Str").setExecutor(new BankCommand(this));
  getCommand("String_Node_Str").setExecutor(new SetCompassCommand());
  getCommand("String_Node_Str").setExecutor(new SetSpawnLocationCommand());
  getCommand("String_Node_Str").setExecutor(new KillFarmAnimalsCommand());
  getCommand("String_Node_Str").setExecutor(new KillHostileMobsCommand());
  getCommand("String_Node_Str").setExecutor(new SpawnMobCommand());
  getCommand("String_Node_Str").setExecutor(new WhoCommand());
  getCommand("String_Node_Str").setExecutor(new TeleportCommand());
  getCommand("String_Node_Str").setExecutor(new SetRankCommand(rankFunctions));
  getCommand("String_Node_Str").setExecutor(new ChestHelpCommand());
  getCommand("String_Node_Str").setExecutor(new GetChestCountCommand(chestFunctions));
  getCommand("String_Node_Str").setExecutor(new UnlockChestCommand(chestFunctions));
  PluginDescriptionFile pdfFile=this.getDescription();
  deathevents.put("String_Node_Str",getConfiguration().getStringList("String_Node_Str",null));
  System.out.println(pdfFile.getName() + "String_Node_Str" + pdfFile.getVersion()+ "String_Node_Str");
  if (!PluginFile.exists()) {
    try {
      new File(maindirectory).mkdir();
      PluginFile.createNewFile();
    }
 catch (    IOException e) {
      e.printStackTrace();
    }
  }
  if (!shopFile.exists()) {
    try {
      new File(maindirectory).mkdir();
      shopFile.createNewFile();
    }
 catch (    IOException e) {
      e.printStackTrace();
    }
  }
}