PlayerInteractEvent NullPointerException

My code works except for one thing. It prints a stacktrace every time an item right clicked is not under the category I want (which has the name "Cougar-Magnem". It gives me a NullPointerException when I do this here is my code.

Code:

public class EventListener extends JavaPlugin implements Listener
{
   
    @EventHandler(priority=EventPriority.NORMAL)
    public void onPlayerUse(PlayerInteractEvent event)
    {
        Player p = event.getPlayer();
     
        if(event.getAction()==(Action.RIGHT_CLICK_BLOCK) || event.getAction() == Action.RIGHT_CLICK_AIR && p.getItemInHand().getItemMeta().getDisplayName().contains(ChatColor.GOLD + "Cougar-Magnem") != (p.getItemInHand().getItemMeta().getDisplayName().contains(ChatColor.GOLD + "Cougar-Magnem Ammo")))
        {
            p.sendMessage("Fired");
        }
       
       
        else if(event.getAction()==(Action.RIGHT_CLICK_BLOCK) || event.getAction()==(Action.RIGHT_CLICK_AIR))
        {
           
        }
       
    }
 
}

 

Check if they have anything in their hand first.

EDIT: i.e. if (p.getItemInHand() != null)

 

I am still getting a NullPointerException when I right click with any other block. Also when I rightclick on a block with air it still prints a message.

 

Really need the stacktrace in this instance, it may not be the code you have given us.

 

Here is the stacktrace

Code:

Caused by: java.lang.NullPointerException
        at com.brendannoble.goldeneye.EventListener.onPlayerUse(EventListener.ja
va:23)
        at sun.reflect.GeneratedMethodAccessor7.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)
        ... 16 more
>

Jnorr44

 

Okay, so I need to know which line is 23, and I also need to see your updated code. (You did put in the p.getItemInHand() != null right?)

 

yes I did Jnorr44

Code:

public class EventListener extends JavaPlugin implements Listener
{
 
    @EventHandler(priority=EventPriority.NORMAL)
    public void onPlayerUse(PlayerInteractEvent event)
    {
        Player p = event.getPlayer();
        {
            if (p.getItemInHand() != null)
            {
[B]    LINE 23[/B]          if(event.getAction()==(Action.RIGHT_CLICK_BLOCK) || event.getAction() == Action.RIGHT_CLICK_AIR && p.getItemInHand().getItemMeta().getDisplayName().contains(ChatColor.GOLD + "Cougar-Magnem") != (p.getItemInHand().getItemMeta().getDisplayName().contains(ChatColor.GOLD + "Cougar-Magnem Ammo")))
                {
                    p.sendMessage("Fired");
                }
             
             
                else if(event.getAction()==(Action.RIGHT_CLICK_BLOCK) || event.getAction()==(Action.RIGHT_CLICK_AIR))
                {
                 
                }
            }
        }
    }
}

 

That if-statement seems to be incorrect, try this:

if((event.getAction()==(Action.RIGHT_CLICK_BLOCK) || event.getAction() == Action.RIGHT_CLICK_AIR) && p.getItemInHand().getItemMeta().getDisplayName().contains(ChatColor.GOLD + "Cougar-Magnem") && !p.getItemInHand().getItemMeta().getDisplayName().contains(ChatColor.GOLD + "Cougar-Magnem Ammo"))

This will make sure the player right-clicks air or right-clicks a block. It also ensures that the player is holding something with "Cougar-Magnem" in it, but not the respective ammunition.

 

I am still having the issue with any other item giving an error

 

Not really sure what you are trying to do... but I cleaned up your code somewhat:

Code:

    @EventHandler(priority = EventPriority.NORMAL) public void onPlayerUse(PlayerInteractEvent event) {
        Player p = event.getPlayer();
        {
            if (p.getItemInHand() != null) {
                if ((event.getAction() == Action.RIGHT_CLICK_BLOCK || event.getAction() == Action.RIGHT_CLICK_AIR) && weirdCheck(p)) {
                    p.sendMessage("Fired");
                } else if (event.getAction() == Action.RIGHT_CLICK_BLOCK || event.getAction() == Action.RIGHT_CLICK_AIR) {
                    //nothing
                }
            }
        }
    }
 
    public boolean weirdCheck(Player p) {
        String displayName = p.getItemInHand().getItemMeta().getDisplayName();
        return displayName.contains("Cougar-Magnem") && !displayName.contains("Cougar-Magnem Ammo");
    }

 

Jnorr44 I am going to have it shoot out firework effects where the player is looking and deal damage if it hits another entity. I am also going to have the item have a cooldown time. I keep getting an error in my console any time another item is right-clicked somewhere.

 

Send me the error...

 

It still give me the same stacktrace that has to do with both methods.

Code:

Caused by: java.lang.NullPointerException
        at com.brendannoble.goldeneye.EventListener.weirdCheck(EventListener.jav
a:32)
        at com.brendannoble.goldeneye.EventListener.onPlayerUse(EventListener.ja
va:21)
        at sun.reflect.GeneratedMethodAccessor12.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)
        ... 16 more
>

 

If line 32 is :

Code:

String displayName = p.getItemInHand().getItemMeta().getDisplayName();

then the item in hand has no item meta,
but if line 32 is:

Code:

return displayName.contains("Cougar-Magnem") && !displayName.contains("Cougar-Magnem Ammo");

then the displayName is null for that itemMeta.

 

So what should I do? Because it still does it Jnorr44

 

inventorman101

Code:

//Untested
//You could change this method name
public boolean weirdCheck(Player player)
{
     ItemStack i = player.getItemInHand();
     if(i == null)return false; // Fail the test if there is no item in hand
     if(!i.hasItemMeta())return false; // Fail the test if item does not have metadata
     ItemMeta im = i.getItemMeta();
     if(!im.hasDisplayName())return false; // Fail the test if the item doesn't have a display name
     String dn = im.getDisplayName();
     return dn.indexOf("Cougar-Magnem") > -1 && dn.indexOf("Cougar-Magnem Ammo") > - 1;
}

 

Technius Thank You it works but it says Fired on Cougar-magnem ammo not just Cougar-Magnem Do I just switch the names around?

EDIT: Also I need this to work for multiple guns not just one so I need to pass in a value somewhere could you put that into the method.

bump

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