[1.12.2] Comparing ItemStack lists

[unassigned]

Hello, I have two ItemStack lists of the same length (that CAN contain ItemStack.Empty), and I want to compare them and see if they are the same. This list can carry duplicates of items. I have some base functionality working, however, with my current code, all duplicates within the recipe are accounted for as one. For example, one of my recipes require 6x Iron Blocks, and 1x Nether Star, however, if the list has 2x Iron Blocks and the 1x Nether Star, it will run. Here is an example of the lists I am comparing:

Current Items:
1xtile.blockIron@0
1xtile.blockIron@0
1xtile.blockIron@0
0xtile.air@0
1xitem.netherStar@0
1xtile.blockIron@0
1xtile.blockIron@0
1xtile.blockIron@0

Needed Items:
1xitem.netherStar@0
1xtile.blockIron@0
1xtile.blockIron@0
1xtile.blockIron@0
1xtile.blockIron@0
1xtile.blockIron@0
1xtile.blockIron@0
0xtile.air@0

 

Here is the current comparison code I have:

            int matches = 0;
            Iterator<ItemStack> iteratorRecipe = recipeList.iterator();
            for(ItemStack ingredient : infusionItems) {
                while(iteratorRecipe.hasNext()){
                    ItemStack recipeReqire = iteratorRecipe.next();
                    if(ItemStack.areItemStackTagsEqual(recipeReqire, ingredient)){
                        iteratorRecipe.remove();
                        matches++;
                    }
                }
            }

 

And here is the whole method for those who need it:

  Reveal hidden contents

    public IResourceInfusion getInfusion(){
        ArrayList<ItemStack> infusionItems = new ArrayList<>();

        for(TileVoidInfuser infuser : getInfusersNear()){
            if(infuser.stack() != null) { infusionItems.add(infuser.stack()); }
        }
        if(infusionItems.size() < 8) return null;

        for(ItemStack[] recipe : VoidUtilsAPI.RESOURCE_MODIFIERS.keySet()){
            ArrayList<ItemStack> recipeList = new ArrayList<>(Arrays.asList(recipe));

            while (recipeList.size() < 8) {
                System.out.println("Adding an Empty Stack to the list!");
                ItemStack stack = ItemStack.EMPTY;
                stack.setCount(0);
                recipeList.add(stack);
            }

            System.out.println(recipeList.size());
            System.out.println("Required Items:");
            for(ItemStack stack : recipeList) { System.out.println(stack); }

            System.out.println(infusionItems.size());
            System.out.println("Have Items:");
            for(ItemStack stack : infusionItems) { System.out.println(stack); }

            int matches = 0;
            Iterator<ItemStack> iteratorRecipe = recipeList.iterator();
            for(ItemStack ingredient : infusionItems) {
                while(iteratorRecipe.hasNext()){
                    ItemStack recipeReqire = iteratorRecipe.next();
                    if(ItemStack.areItemStackTagsEqual(recipeReqire, ingredient)){
                        iteratorRecipe.remove();
                        matches++;
                    }
                }
            }

            if(matches == 8) return VoidUtilsAPI.RESOURCE_MODIFIERS.get(recipe);

        }

        return null;
    }

 

 

 

Thanks!

[Cadiboo]

  On 12/30/2018 at 9:27 PM, unassigned said:

if(ItemStack.areItemStackTagsEqual(recipeReqire, ingredient)){

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Tags don’t include size, you also want to check the size/count of the ItemStack. I believe that ItemStack provides you with a method for this but if it doesn’t you can do it yourself with ItemStack#getCount

[unassigned]

  On 12/30/2018 at 11:02 PM, Cadiboo said:

Tags don’t include size, you also want to check the size/count of the ItemStack. I believe that ItemStack provides you with a method for this but if it doesn’t you can do it yourself with ItemStack#getCount

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Well, they are all 1 in size. How this works is that it gets a list of items from surrounding 'infusers', which can only hold one item. So I need to compare the lists against each other, to make sure each element matches (excluding order). However, as standard collection sorting doesn't work on ItemStacks, I'm stumped.

[Cadiboo]

  On 12/30/2018 at 9:27 PM, unassigned said:

if(infuser.stack() != null)

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ItemStacks are never null

 

So it works with this?

Actual Items:
1xitem.netherStar@0
1xtile.blockIron@0
1xtile.blockIron@0
0xtile.air@0
0xtile.air@0
0xtile.air@0
0xtile.air@0
0xtile.air@0

[unassigned]

  On 12/30/2018 at 11:14 PM, Cadiboo said:

ItemStacks are never null

  

So it works with this?

Actual Items:
1xitem.netherStar@0
1xtile.blockIron@0
1xtile.blockIron@0
0xtile.air@0
0xtile.air@0
0xtile.air@0
0xtile.air@0
0xtile.air@0

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Yes, as long as there are 1 or more nether star and 2 or more iron blocks.

Here is the recipe being registered

  Reveal hidden contents

        VoidUtilsAPI.addDuplicatableItem(new ItemStack[]{new ItemStack(Items.NETHER_STAR), new ItemStack(Blocks.IRON_BLOCK),
                        new ItemStack(Blocks.IRON_BLOCK), new ItemStack(Blocks.IRON_BLOCK), new ItemStack(Blocks.IRON_BLOCK),
                        new ItemStack(Blocks.IRON_BLOCK), new ItemStack(Blocks.IRON_BLOCK)},
                new ResourceInfusion(new ItemStack(Items.IRON_INGOT), 100000, 0.01f, 5));

 

 

 

[vhbob]

If you iterate through the actual items list and check to see if the recipe list contains that item, and add 1 to the counter, that should work, no?

[unassigned]

  On 12/30/2018 at 11:33 PM, vhbob said:

If you iterate through the actual items list and check to see if the recipe list contains that item, and add 1 to the counter, that should work, no?

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Well, I have to remove the result, otherwise, it will not know if the duplicate items have been checked, thus 1 item would throw the counter up and return true.

Edited December 31, 2018 by unassigned

[unassigned]

  On 12/31/2018 at 1:22 AM, diesieben07 said:

Well, first of all, is this is a "shaped" recipe or a "shapeless" one? I.e., does the position of the stacks in the list matter, or not?

 

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This is considered a shapless recipe, as the order does not matter. (including within the list)

 

  On 12/31/2018 at 1:22 AM, diesieben07 said:

 Also, do excess input items cause the recipe to fail (e.g.: Input is 3 stone and 1 dirt, recipe is just 2 stone, does it still apply)?

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Yes, if there is an item that does not belong, the process should be stopped.

[unassigned]

  On 12/31/2018 at 3:05 PM, diesieben07 said:

Okay. Here is your process:

1. Clone the required ingredient list (deep clone, i.e. you need to clone the stacks within it, too).
2. Loop through the presented input list:
   1. Try to find a match for the current input stack in the cloned ingredient list and modify the count of the stack in the cloned ingredient list accordingly (i.e. if input stack is 3 Stone and 5 Stone is required, change the 5 to a 2).
   2. If you don't find a match, abort (something was presented that is not required).
3. After you are done with all presented input the recipe matches if and only if the cloned ingredient lists contains only empty stacks.

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Okay, I went against what you said (even though it's probably better) and ended up switching to use ingredients, made an actual class that handles the items, and it is working now. However, I'd like to post my result to see how this can be improved, as I'm sure by the way it looks, there is a better way.

        if (!input.apply(in)) return false;
        List<Ingredient> matches = new ArrayList<>();
        ItemStack[] stacks = { infuser1, infuser2, infuser3, infuser4, infuser5, infuser6, infuser7, infuser8 };
        boolean[] unused = { true, true, true, true, true, true, true, true };
        for (ItemStack s : stacks) {
            if (unused[0] && modifier1.apply(s)) {
                matches.add(modifier1);
                unused[0] = false;
            } else if (unused[1] && modifier2.apply(s)) {
                matches.add(modifier2);
                unused[1] = false;
            } else if (unused[2] && modifier3.apply(s)) {
                matches.add(modifier3);
                unused[2] = false;
            } else if (unused[3] && modifier4.apply(s)) {
                matches.add(modifier4);
                unused[3] = false;
            } else if (unused[4] && modifier5.apply(s)) {
                matches.add(modifier2);
                unused[4] = false;
            } else if (unused[5] && modifier6.apply(s)) {
                matches.add(modifier3);
                unused[5] = false;
            } else if (unused[6] && modifier7.apply(s)) {
                matches.add(modifier4);
                unused[6] = false;
            } else if (unused[7] && modifier8.apply(s)) {
                matches.add(modifier4);
                unused[7] = false;
            }
        }

        return matches.size() == 8;

As I said, I went from supplying an array of ItemStack for the ingredients, to just having 8 separate ingredients and checking them.  

[Draco18s]

  On 1/3/2019 at 5:13 AM, unassigned said:

} else if

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Dear sweet jebus chritie.

 

DRY!

Fek.

[Cadiboo]

Wouldn't it be amazing if Java had switch statements or loops...

[unassigned]

  On 1/4/2019 at 10:04 AM, Cadiboo said:

Wouldn't it be amazing if Java had switch statements or loops...

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  On 1/3/2019 at 6:07 PM, Draco18s said:

Dear sweet jebus chritie.

 

DRY!

Fek.

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haha, I was just trying to get a visual, I meant to change this with for loop before posting, but I wanted to see if there was anything better functional wise (ex. more optimized). However, for those interested here is what it looks like now:

    public boolean matches(ItemStack in, ItemStack infuser1, ItemStack infuser2, ItemStack infuser3, ItemStack infuser4,
                           ItemStack infuser5,ItemStack infuser6,ItemStack infuser7,ItemStack infuser8){

        if (!input.apply(in)) return false;
        
        List<Ingredient> matches = new ArrayList<>();
        ItemStack[] stacks = { infuser1, infuser2, infuser3, infuser4, infuser5, infuser6, infuser7, infuser8 };
        Ingredient[] ingredients = { modifier1, modifier2, modifier3, modifier4, modifier5, modifier6, modifier7, modifier8 };
        boolean[] unused = { true, true, true, true, true, true, true, true };
        
        for (ItemStack s : stacks) {
            for(int i = 0; i < ingredients.length; i++) {
                if(unused[i] && ingredients[i].apply(s)){
                    matches.add(ingredients[i]);
                    unused[i] = false;
                }
            }
        }
        
        return matches.size() == 8;
    }

Thanks.

[Cadiboo]

  On 1/4/2019 at 10:31 PM, unassigned said:

boolean[] unused = { true, true, true, true, true, true, true, true };

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personally I would do something like `final boolean[] used = new boolean[8]`

[larsgerrits]

  On 1/5/2019 at 10:17 AM, Cadiboo said:

personally I would do something like `final boolean[] used = new boolean[8]`

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That would make all the booleans false by default.

[Cadiboo]

  On 1/7/2019 at 9:03 PM, larsgerrits said:

That would make all the booleans false by default.

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That was the point, their using a boolean array called unused that is initialised to true, I would use a boolean array called used that is automatically initialised to false

[Draco18s]

  On 1/7/2019 at 9:03 PM, larsgerrits said:

That would make all the booleans false by default.

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So...invert the rest of your logic that deals with the field.