How is this null?!

when i do vault open i get a null pointer on line 55 which is p.openInventory(backpacks.get(p.getName()));

heres the code for that stuff

Command

Code:

  if (cmd.equalsIgnoreCase("open")){
                    if(args.length == 1){        // |
                        //Error NullPointer Line 55 \/
                        if(backpacks != null) {
                            if(p.getName() != null) {
                                    p.openInventory(backpacks.get(p.getName()));
                                }
                        }
                    }
                    else {
                        p.sendMessage(MOREARGS);
                    }
                }

HashMap

Code:

 private HashMap<String, Inventory> backpacks = new HashMap<String, Inventory>();

Listeners

Code:

 @EventHandler
    public void onPlayerJoin(PlayerJoinEvent e) {
        Inventory inv = Bukkit.getServer().createInventory(e.getPlayer(), 27, ChatColor.GREEN + e.getPlayer().getName() + "'s Vault");

        if (plugin != null) {
            if (plugin.getConfig() != null) {
                if (plugin.getConfig().contains("backpacks." + e.getPlayer().getName())) {
                    for (String item : plugin.getConfig().getConfigurationSection("backpacks." + e.getPlayer().getName()).getKeys(false)) {
                        inv.addItem(loadItem(plugin.getConfig().getConfigurationSection("backpacks." + e.getPlayer().getName() + "." + item)));
                    }
                }
                backpacks.put(e.getPlayer().getName(), inv);
            }
        }
    }
    @EventHandler
    public void onPlayerLeave(PlayerQuitEvent e) {
        if (!plugin.getConfig().contains("backpacks." + e.getPlayer().getName())) {
            plugin.getConfig().createSection("backpacks." + e.getPlayer().getName());
        }

        char c = 'a';
        for (ItemStack itemStack : backpacks.get(e.getPlayer().getName())) {
            if (itemStack != null) {
                saveItem(plugin.getConfig().createSection("backpacks." + e.getPlayer().getName() + "." + c++), itemStack);
            }
        }

        plugin.saveConfig();
    }

    private void saveItem(ConfigurationSection section, ItemStack itemStack) {
        section.set("type", itemStack.getType().name());
        section.set("amount", itemStack.getAmount());
        // Save more information.
    }

    private ItemStack loadItem(ConfigurationSection section) {
        return new ItemStack(Material.valueOf(section.getString("type")), section.getInt("amount"));
        // Load more information.
    }
}

 

Does backpack contain player?

 

Why didn't you post the error? I can GUESS that backpacks doesn't have an Inventory mapped to the player name in question.