Solved if player has one out of a list of items. take one

Hello again.

So basically there's a list of items and then if the player has some of the items then take ONLY one item out of that list. So like: If the list of items contains apple, sapling, coal. The player has said items. What I want it to do is then take only ONE of those items e.g take the apple and then leave the sapling and the coal. If the player then has a grass block and a piston then only take the piston and leave the grass block, but if he didn't have the piston then it should've taken the grass block.

It's very hard to explain, but I hope some of you understand it ^^

Thank you!

Don't leave me hanging. Bump xC

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

 

To remove ALL apples IF the player has one:

Code:java

            if (player.getInventory().contains(new ItemStack(Material.APPLE))){
                player.getInventory().remove(new ItemStack(Material.APPLE));
            }

To only remove 1 of the several stacks of apples, either use the slot int, removing the first, or using Java Math Random to remove an apple in a random slot.

 

But what I want is to remove one item out of a list of items. I know how to remove the apple, but what if people have an apple, a bread and a cake. I want it to only remove one of those items, BUT if he didn't have an apple then it would remove one of the other items

 

You could iterate over your list of those items, be it the item type of the actual item stack, check if the player has one of it in the inventory, remove it and then just exit the loop.

 

I understand your logic, but how would I go about doing that?
Like this?:

Code:java

Material[] energy = { Material.SAPLING, Material.RED_ROSE, Material.CACTUS, Material.BROWN_MUSHROOM, Material.COAL , Material.YELLOW_FLOWER, Material.SUGAR_CANE, Material.SEEDS};
 
for(Material m : energy) {
if(p.getInventory().contains(m)) {
 
}
}

ow would I go about stopping it when it finds one of said items?

 

You should be familiar with the break statement. http://docs.oracle.com/javase/tutorial/java/nutsandbolts/branch.html

 

Ooooh yea, sorry didn't think of that! Thanks

EDIT:
How come this doesn't work?

Code:java

    public void takeEnergy(Player p){
        Material[] energy = { Material.SAPLING, Material.RED_ROSE, Material.CACTUS, Material.BROWN_MUSHROOM, Material.COAL , Material.YELLOW_FLOWER, Material.SUGAR_CANE, Material.SEEDS};
 
        for(Material m : energy) {
            if(p.getInventory().contains(m)) {
            hasEnergy = true;
            break;
            }else{
                hasEnergy = false;
            }
            if(hasEnergy){
                p.getInventory().remove(m);
            }
        }

 

Try

PHP:

public void takeEnergy(Player p){
Material[] energy = { Material.SAPLING, Material.RED_ROSE, Material.CACTUS, Material.BROWN_MUSHROOM, Material.COAL , Material.YELLOW_FLOWER, Material.SUGAR_CANE, Material.SEEDS};
 
for(Material m : energy) {
if(p.getInventory().contains(m)) {
hasEnergy = true;
break;
}else{
hasEnergy = false;
}
if(hasEnergy == true){
p.getInventory().remove(m);
}
}

but, this will remove all items (I think)

 

Nope it doesn't work :/ Thanks anyway.

 

You're checking if hasEnergy is true inside the loop, however you immediately exit the loop when you set it to true. so either do the if content directly when you set hasEnergy or do it outside of the loop.

 

But if I put it outside the loop it doesn't know what Material m is. So how will I remove the item found?

 

Then do it this way:

 

Sorry I don't quite get it

Edit:
You mean like this:

Code:java

    public void takeEnergy(Player p){
        Material[] energy = { Material.SAPLING, Material.RED_ROSE, Material.CACTUS, Material.BROWN_MUSHROOM, Material.COAL , Material.YELLOW_FLOWER, Material.SUGAR_CANE, Material.SEEDS};
 
        for(Material m : energy) {
        if(p.getInventory().contains(m)) {
            p.getInventory().remove(m);
        hasEnergy = true;
        break;
        }else{
        hasEnergy = false;
        }
        }
    }

?

 

I guess that would work, just try it out.

 

Arg, it did not work. Maybe I should just give up doing it this way.

Edit:
It got it to work, but it takes the whole stack of the item. Is there anyway for it to only take perhaps one?

 

When the amount is 1 still remove it, else just set the amount one less.

 

Sorry for being a bit thick headed, but could you explain that again, or give me an example?

 

By that I mean altering the amount of the items in the stack.
http://jd.bukkit.org/rb/doxygen/d9/...mStack.html#ab0cac4c14b2eb5e11543ae64bacf8359
When there's only one, you can remove it, but when there are more, just remove one from the stack, thus removing one from the amount.

 

Was it this you were thinking?:

Code:java

        for(Material m : energy) {
        if(p.getInventory().contains(m)) {
        hasEnergy = true;
        ItemStack is = new ItemStack(m);
        if(is.getAmount() == 1){
            p.getInventory().remove(is);
        }else{
            p.getInventory().remove(is.getAmount() - 1);
        }
        p.updateInventory();
        break;
        }else{
        hasEnergy = false;
        }
        }

That doesn't seem to work, though.

 

Not exactly, since when you create a new instance of the itemstack it won't affect the itemstack which is currently in your inventory. I would prefer looping though all the inventory items and for each item check if it's one of your materials, if so, change the amount or remove it (because of this, you're better of using an iterator).

 

Yea, now I'm completely lost. Sorry xC

 

Code:

iterator = inventory.iterator
while iterator.hasNext
{
  item = iterator.next
  found = false
  foreach type in myMaterials
  {
      is item.ofType type ?
      {
          found = true
          is item.amount == 1 ?
              iterator.remove
          otherwise
              item.amount = item.amount - 1
          break
       }
     
      is found ?
          break
  }
}

 

Code:java

        Iterator i = p.getInventory().iterator();
        while(i.hasNext()){
            ItemStack mat = (ItemStack) i.next();
            //For each type? What
            //hasEnergy = true;
            if(mat.getAmount() == 1){
                i.remove();
            }else{
              p.getInventory().remove(mat.getAmount() - 1);
              break;
            }
            if(hasEnergy == true){
                break;
            }
        }

This is what I could get out of it. Some things I'm a bit confused by. Is it right? And what's the for Each type thing?
Also I really appreciate that you want to go through all this with me! I'm very grateful.

 

Foreach is well.. for each. So for each x in a collection/array do the given thing.

 

Eeeeeh, what? You mean a for(mat.getType()){ ??

 

for(Material mat : yourmaterials) this is technically a foreach.

 

Code:java

    public void takeEnergy(Player p){
        Material[] energy = { Material.SAPLING, Material.RED_ROSE, Material.CACTUS, Material.BROWN_MUSHROOM, Material.COAL , Material.YELLOW_FLOWER, Material.SUGAR_CANE, Material.SEEDS};
        hasEnergy = false;
        Iterator i = p.getInventory().iterator();
        while(i.hasNext()){
            ItemStack mat = (ItemStack) i.next();
            for(Material ma: energy){
            hasEnergy = true;
            if(mat.getAmount() == 1){
                i.remove();
            }else{
              p.getInventory().remove(mat.getAmount() - 1);
              break;
            }
            }
            if(hasEnergy == true){
                break;
            }
        }
    }

Sorry for answering late, but this doesn't seem to work

 

Because you forgot something, because now it sets 'hasEngergy' true, without checking the type/material of it.

 

Code:

    public void takeEnergy(Player p){
        Material[] energy = { Material.SAPLING, Material.RED_ROSE, Material.CACTUS, Material.BROWN_MUSHROOM, Material.COAL , Material.YELLOW_FLOWER, Material.SUGAR_CANE, Material.SEEDS};
        hasEnergy = false;
        Iterator i = p.getInventory().iterator();
        while(i.hasNext()){
            ItemStack mat = (ItemStack) i.next();
            for(Material ma: energy){
            if(mat.getAmount() == 1){
                hasEnergy = true; //This
                i.remove();
            }else{
                hasEnergy = true; //This
              p.getInventory().remove(mat.getAmount() - 1);
              break;
            }
            }
            if(hasEnergy == true){
                break;
            }
        }
    }

Tried to do this, but it didn't work D:

 

Nononono. Why are you getting the material amount?
Think about what you want. You want to check if the current itemstack has one of the given materials. The check for the amount comes later when you actually know that it is of one of your materials.