Program: 41992
Project: 41992
Buggy source:
public boolean execute(ICommandSender sender,String[] args) throws Exception {
  if (args.length < 2 && args.length >= 3) {
    throw new BadUsageException(getUsage());
  }
  if (args[1].length() > 16 || !validUserPattern.matcher(args[1]).matches()) {
    throw new IllegalArgumentException(C("String_Node_Str"));
  }
  if ("String_Node_Str".equalsIgnoreCase(args[1]) && plugin.getConfig().getBoolean("String_Node_Str")) {
    sender.sendMessage("String_Node_Str");
    return true;
  }
  IPlayer player=(IPlayer)sender;
  if (player.hasPermission(PermissionNames.ADMIN_DENY) || player.hasPermission(PermissionNames.USER_DENY)) {
    IWorld world=player.getWorld();
    if (manager.isPlotWorld(world)) {
      PlotId id=manager.getPlotId(player);
      if (id == null) {
        player.sendMessage(C("String_Node_Str"));
        return true;
      }
      PlotMapInfo pmi=manager.getMap(world);
      if (!manager.isPlotAvailable(id,pmi)) {
        Plot plot=manager.getPlotById(id,pmi);
        String denied=args[1];
        if (player.getUniqueId().equals(plot.getOwnerId()) || player.hasPermission(PermissionNames.ADMIN_DENY)) {
          if (plot.getOwner().equalsIgnoreCase(denied)) {
            player.sendMessage(C("String_Node_Str"));
            return true;
          }
          if (plot.isDeniedConsulting(denied)) {
            player.sendMessage(C("String_Node_Str") + "String_Node_Str" + args[1]+ "String_Node_Str"+ C("String_Node_Str"));
          }
 else {
            double price=0.0;
            PlotAddDeniedEvent event=new PlotAddDeniedEvent(world,plot,player,denied);
            if (manager.isEconomyEnabled(pmi)) {
              price=pmi.getDenyPlayerPrice();
              if (serverBridge.has(player,price)) {
                serverBridge.getEventBus().post(event);
                if (event.isCancelled()) {
                  return true;
                }
                EconomyResponse er=serverBridge.withdrawPlayer(player,price);
                if (!er.transactionSuccess()) {
                  player.sendMessage(er.errorMessage);
                  serverBridge.getLogger().warning(er.errorMessage);
                  return true;
                }
              }
 else {
                player.sendMessage(C("String_Node_Str") + "String_Node_Str" + C("String_Node_Str")+ "String_Node_Str"+ serverBridge.getEconomy().format(price));
                return true;
              }
            }
 else {
              serverBridge.getEventBus().post(event);
            }
            if (!event.isCancelled()) {
              plot.addDenied(denied);
              plot.removeAllowed(denied);
              if ("String_Node_Str".equals(denied)) {
                List<IPlayer> playersInPlot=manager.getPlayersInPlot(id,world);
                for (                IPlayer iPlayer : playersInPlot) {
                  if (!plot.isAllowed(iPlayer.getUniqueId())) {
                    iPlayer.setLocation(manager.getPlotHome(plot.getId(),player.getWorld()));
                  }
                }
              }
 else {
                IPlayer deniedPlayer=serverBridge.getPlayer(denied);
                if (deniedPlayer != null && deniedPlayer.getWorld().equals(world)) {
                  PlotId plotId=manager.getPlotId(deniedPlayer);
                  if (plotId.equals(id)) {
                    deniedPlayer.setLocation(manager.getPlotHome(plot.getId(),player.getWorld()));
                  }
                }
              }
              player.sendMessage(C("String_Node_Str") + "String_Node_Str" + denied+ "String_Node_Str"+ C("String_Node_Str")+ "String_Node_Str"+ serverBridge.getEconomy().format(price));
              if (isAdvancedLogging()) {
                if (price == 0) {
                  serverBridge.getLogger().info(player.getName() + "String_Node_Str" + C("String_Node_Str")+ "String_Node_Str"+ denied+ "String_Node_Str"+ C("String_Node_Str")+ "String_Node_Str"+ id);
                }
 else {
                  serverBridge.getLogger().info(player.getName() + "String_Node_Str" + C("String_Node_Str")+ "String_Node_Str"+ denied+ "String_Node_Str"+ C("String_Node_Str")+ "String_Node_Str"+ id+ ("String_Node_Str" + C("String_Node_Str") + "String_Node_Str"+ price));
                }
              }
            }
          }
        }
 else {
          player.sendMessage(C("String_Node_Str") + "String_Node_Str" + id+ "String_Node_Str"+ C("String_Node_Str"));
        }
      }
 else {
        player.sendMessage(C("String_Node_Str") + "String_Node_Str" + id+ "String_Node_Str"+ C("String_Node_Str"));
      }
    }
 else {
      player.sendMessage(C("String_Node_Str"));
    }
  }
 else {
    return false;
  }
  return true;
}

Fixed version (ground truth):
public boolean execute(ICommandSender sender,String[] args) throws Exception {
  if (args.length < 2 && args.length >= 3) {
    throw new BadUsageException(getUsage());
  }
  if (args[1].length() > 16 || !validUserPattern.matcher(args[1]).matches()) {
    throw new IllegalArgumentException(C("String_Node_Str"));
  }
  if ("String_Node_Str".equals(args[1]) && plugin.getConfig().getBoolean("String_Node_Str")) {
    sender.sendMessage("String_Node_Str");
    return true;
  }
  IPlayer player=(IPlayer)sender;
  if (player.hasPermission(PermissionNames.ADMIN_DENY) || player.hasPermission(PermissionNames.USER_DENY)) {
    IWorld world=player.getWorld();
    if (manager.isPlotWorld(world)) {
      PlotId id=manager.getPlotId(player);
      if (id == null) {
        player.sendMessage(C("String_Node_Str"));
        return true;
      }
      PlotMapInfo pmi=manager.getMap(world);
      if (!manager.isPlotAvailable(id,pmi)) {
        Plot plot=manager.getPlotById(id,pmi);
        String denied=args[1];
        if (player.getUniqueId().equals(plot.getOwnerId()) || player.hasPermission(PermissionNames.ADMIN_DENY)) {
          if (plot.getOwner().equals(denied)) {
            player.sendMessage(C("String_Node_Str"));
            return true;
          }
          if (plot.isDeniedConsulting(denied)) {
            player.sendMessage(C("String_Node_Str") + "String_Node_Str" + args[1]+ "String_Node_Str"+ C("String_Node_Str"));
          }
 else {
            double price=0.0;
            PlotAddDeniedEvent event=new PlotAddDeniedEvent(world,plot,player,denied);
            if (manager.isEconomyEnabled(pmi)) {
              price=pmi.getDenyPlayerPrice();
              if (serverBridge.has(player,price)) {
                serverBridge.getEventBus().post(event);
                if (event.isCancelled()) {
                  return true;
                }
                EconomyResponse er=serverBridge.withdrawPlayer(player,price);
                if (!er.transactionSuccess()) {
                  player.sendMessage(er.errorMessage);
                  serverBridge.getLogger().warning(er.errorMessage);
                  return true;
                }
              }
 else {
                player.sendMessage(C("String_Node_Str") + "String_Node_Str" + C("String_Node_Str")+ "String_Node_Str"+ serverBridge.getEconomy().format(price));
                return true;
              }
            }
 else {
              serverBridge.getEventBus().post(event);
            }
            if (!event.isCancelled()) {
              plot.addDenied(denied);
              plot.removeAllowed(denied);
              if ("String_Node_Str".equals(denied)) {
                List<IPlayer> playersInPlot=manager.getPlayersInPlot(id,world);
                for (                IPlayer iPlayer : playersInPlot) {
                  if (!plot.isAllowed(iPlayer.getUniqueId())) {
                    iPlayer.setLocation(manager.getPlotHome(plot.getId(),player.getWorld()));
                  }
                }
              }
 else {
                IPlayer deniedPlayer=serverBridge.getPlayer(denied);
                if (deniedPlayer != null && deniedPlayer.getWorld().equals(world)) {
                  PlotId plotId=manager.getPlotId(deniedPlayer);
                  if (plotId.equals(id)) {
                    deniedPlayer.setLocation(manager.getPlotHome(plot.getId(),player.getWorld()));
                  }
                }
              }
              player.sendMessage(C("String_Node_Str") + "String_Node_Str" + denied+ "String_Node_Str"+ C("String_Node_Str")+ "String_Node_Str"+ serverBridge.getEconomy().format(price));
              if (isAdvancedLogging()) {
                if (price == 0) {
                  serverBridge.getLogger().info(player.getName() + "String_Node_Str" + C("String_Node_Str")+ "String_Node_Str"+ denied+ "String_Node_Str"+ C("String_Node_Str")+ "String_Node_Str"+ id);
                }
 else {
                  serverBridge.getLogger().info(player.getName() + "String_Node_Str" + C("String_Node_Str")+ "String_Node_Str"+ denied+ "String_Node_Str"+ C("String_Node_Str")+ "String_Node_Str"+ id+ ("String_Node_Str" + C("String_Node_Str") + "String_Node_Str"+ price));
                }
              }
            }
          }
        }
 else {
          player.sendMessage(C("String_Node_Str") + "String_Node_Str" + id+ "String_Node_Str"+ C("String_Node_Str"));
        }
      }
 else {
        player.sendMessage(C("String_Node_Str") + "String_Node_Str" + id+ "String_Node_Str"+ C("String_Node_Str"));
      }
    }
 else {
      player.sendMessage(C("String_Node_Str"));
    }
  }
 else {
    return false;
  }
  return true;
}