verybad.java

@EventHandler
  public void onPlayerBreak(BlockBreakEvent e) {
    Player player = e.getPlayer();
    
    File rankFile = new File(String.valueOf(this.m.fileLoc) + "Ranks" + ".yml");
    File playerFile = new File(String.valueOf(this.m.fileLoc) + "Players" + ".yml");
    YamlConfiguration rankYaml = new YamlConfiguration();
    YamlConfiguration playerYaml = new YamlConfiguration();
    
    try {
      rankYaml.load(rankFile);
      playerYaml.load(playerFile);
      
      String rank = playerYaml.getString("players." + player.getUniqueId());
      boolean canBuild = rankYaml.getBoolean("Groups." + rank + ".build");
      e.setCancelled(!canBuild);
    } catch (Exception e1) {
      e1.printStackTrace();
    } 
  }