ItemStack NPE?

Code:

Caused by: java.lang.NullPointerException
        at org.bukkit.inventory.ItemStack.<init>(ItemStack.java:64)
        at me.moxie.util.LevelUpEvent.reward(LevelUpEvent.java:141)
        at me.moxie.util.LevelUpEvent.levelUp(LevelUpEvent.java:35)
        at me.moxie.XPlisteners.SwordXP.SwordsXPProcess(SwordXP.java:63)
        at me.moxie.XPlisteners.SwordXP.EntityDeath(SwordXP.java:42)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.lang.reflect.Method.invoke(Unknown Source)
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:425)
        ... 21 more

That's the error I get, now the code it relates to is this:

Code:

for(int i : t.keySet()){
                    if((lvl % i)==0 || i == 1){
                        check=true;
                        String s = t.get(i);
                        String[] x = s.split(",");
                        String type = x[0];
                        String ID = x[1];
                        Integer amount = Integer.parseInt(x[2]);
                        if(type.equalsIgnoreCase("item")){
                            p.getInventory().addItem(new ItemStack(Material.getMaterial(ID), amount));
                            p.sendMessage(ChatColor.GOLD+"You received a reward: " + ChatColor.GREEN+amount+" " + Material.getMaterial(ID).toString().toLowerCase());
                        } else if(type.equalsIgnoreCase("xp")){
                            p.setTotalExperience(p.getTotalExperience()+amount);
                            p.sendMessage(ChatColor.GOLD+"You received a reward: " + ChatColor.GREEN+amount+" XP");
                        } else if(type.equalsIgnoreCase("money")){
                            if(this.m.EconomyEnabled==false)
                                return;
                            Moxie.economy.depositPlayer(p.getName(), amount);
                            p.sendMessage(ChatColor.GOLD+"You received a reward: " + ChatColor.GREEN+amount+" " + Moxie.economy.currencyNamePlural());
                        }
                    }
                }

I have checked both ID and amount, and they produce the values 89 and 3 as expected, which should mean the itemstack added is 3 glowstone. Yet I get that error. Any help please?

 

Specifically which line is the error related to?

 

Ne0nx3r0

p.getInventory().addItem(new ItemStack(Material.getMaterial(ID), amount));
It says this line gives the NPE

 

The way I usually troubleshoot these is by checking the variables individually and after they are grabbed from methods, so something like:

Code:

System.out.println(p);
System.out.println(p.getInventory());
System.out.println(ID);
System.out.println(amount);
System.out.println(Material.getMaterial(ID));

Assuming the cause of the error is coming from that line, and not someplace higher/lower in the stacktrace.

 

Ne0nx3r0

Aha!

Code:

System.out.println(Material.getMaterial(ID));

This is what returns null, but surely it should be fine as the ID is 89 - glowstone, it should be able to "get" that right?

 

Try changing ID from a String to an int, something like:

Code:

int ID;
try
{
      ID = Integer.parseInt(x[1]);
}
catch (Exception e)
{
    // Not a valid int
}

*edit*

Notably, here's a code sample I've used in the past to first match a string (IE: "glowstone", then attempt to convert to an int and try 89):

Code:

        Material m = null;
        try {
          m = Material.getMaterial(Integer.parseInt(args[0]));
        } catch (Exception e) {
          m = Material.matchMaterial(args[0]);
 
          if ((m == null) || (!m.isBlock())) {
            this.p.msg(player, ChatColor.RED + "'" + args[0] + "' is not a valid block!");
            this.p.msg(player, "(hint: diamond_block vs diamond)");
            return true;
          }
        }

 

Ne0nx3r0

Ah! Now you say it that way, it does seem like a possible reason! I'll try it out now!

Ne0nx3r0

Worked, thanks!

EDIT by Moderator: merged posts, please use the edit button instead of double posting.