# Must qualify the allocation with

**URL:** <https://discourse.processing.org/t/must-qualify-the-allocation-with/2828>\
**Category:** Coding Questions\
**Created:** [August 22, 2018, 12:10am UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828 "2018-08-22T00:10:17Z")\
**Posts on this page:** 20\
**Page:** 1

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 12:10am UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/1 "2018-08-22T00:10:17Z")

</div>

I google this problem but otehr one sort out!  
I cannot create a new instance of one of my class, here is the main:

```auto
Snake snake;
A tmp;

int frameSpeed = 1;//the frame rate
int score = 0;
//int bestScore = 0;
int attempts = 1;
Population pop;
int amountOfSnakes = 200;

void setup()
{//on startup
  size(600, 800);
  frameRate(frameSpeed);  
  tmp = new A();
  snake = new Snake();  
  pop = new Population(amountOfSnakes);// create new population of size 200  
}

void draw() {
  background(40);
  fill(255);
etc...
etc...
etc...

```

Well, A and Snake class had been created with no error but new Population not!  
Snake and A are non-statich class, Population is a static class!!!  
Help, im struggling with no clue or result!

---

<div class="post-metadata">

**Author:** ![Kevin](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/kevin/32/2297_2.png) [@Kevin](https://discourse.processing.org/u/Kevin)\
**Post date:** [August 22, 2018, 12:12am UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/2 "2018-08-22T00:12:03Z")

</div>

Can you please post a [small example program](https://stackoverflow.com/help/mcve) that demonstrates the problem? Note that this should not be your full sketch, but it should be enough for us to copy and paste to see ourselves.

You can find more info in this guide:

> [@Guidelines—Asking Questions](https://discourse.processing.org/t/guidelines-tips-on-asking-questions/2147):
>
> Summary (TL;DR) Ask complete questions to get better answers! Be specific. For example: I want to load an image. I tried using createImg() , and I expected the image to be on canvas, but what happened instead was the image showing up below the canvas. Isolate your problem and work in small steps. Share only the code directly related to your problem if it is part of a bigger project, and if something isn’t working, try the smallest code that could do the thing you want. Can we run your code to …

---

<div class="post-metadata">

**Author:** ![TheWizardBear](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/thewizardbear/32/3552_2.png) [@TheWizardBear](https://discourse.processing.org/u/TheWizardBear)\
**Post date:** [August 22, 2018, 8:08am UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/3 "2018-08-22T08:08:57Z")

</div>

Can we see the population class–or at least the most important bits.

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<div class="post-metadata">

**Author:** ![quark](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/quark/32/26_2.png) [@quark](https://discourse.processing.org/u/quark)\
**Post date:** [August 22, 2018, 3:47pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/4 "2018-08-22T15:47:22Z")

</div>

We also need to know the actual error message provided by Processing.

---

<div class="post-metadata">

**Author:** ![EnhancedLoop7](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/enhancedloop7/32/1040_2.png) [@EnhancedLoop7](https://discourse.processing.org/u/EnhancedLoop7)\
**Post date:** [August 22, 2018, 6:00pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/5 "2018-08-22T18:00:12Z")

</div>

**EDIT**

I’m sorry I did not see that you had declared it already! I will continue looking at your code, but I’ll keep my original explanation in case if someone else has a sort of similar problem 😅

As of now, I would like to also ask that you post a little more about your problem, so that we could help out further!

**Original Response:**

From what you posted, take a look at the top of your code:

```auto
Snake snake;
A tmp;

```

Looks like A and Snake are the only ones working, because it seems that those are the only ones that you actually _declared_ 😃

Just add **this** to the top of your code:

`Population pop;`

To match what you have here in `setup()` :

`pop = new Population(amountOfSnakes);`

You need to make sure you declare a variable or class before you can actually try to use it and such. If Processing is saying something like “Must qualify the allocation” that means that you are trying to initialize a variable, in this case: pop, and you didn’t even allocate any memory to it by declaring it yet! It’s easy to forget especially if you build the class first, but yes always remember to declare your objects up top, trust me- I’ve been there too 😂

Hope that clears it up!

EnhancedLoop7

---

<div class="post-metadata">

**Author:** ![TfGuy44](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/tfguy44/32/41_2.png) [@TfGuy44](https://discourse.processing.org/u/TfGuy44)\
**Post date:** [August 22, 2018, 6:03pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/6 "2018-08-22T18:03:39Z")

</div>

> [@Manatee](#):
>
> ```auto
> ...
> int attempts = 1;
> Population pop;
> int amountOfSnakes = 200;
> ...
> 
> ```

He had it all along!

---

<div class="post-metadata">

**Author:** ![neilcsmith](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/neilcsmith/32/144_2.png) [@neilcsmith](https://discourse.processing.org/u/neilcsmith)\
**Post date:** [August 22, 2018, 6:44pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/7 "2018-08-22T18:44:41Z")

</div>

_Why_ is Population static and the others not? Does it work if it isn’t static?

---

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 7:09pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/8 "2018-08-22T19:09:12Z")

</div>

Give me some times, Im working on to reply to all of you!

---

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 7:46pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/9 "2018-08-22T19:46:54Z")

</div>

I apologize with everybody!  
I solved my problem adjusting the folder name with the class that hold the “main” structurre (setup() and draw()) and now it starts to work again!  
So the problem was 75% a folder problem solved changed main class name and folder name!  
Thank you all for fast reply and super help!

---

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 7:49pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/10 "2018-08-22T19:49:25Z")

</div>

It works yes with static and not.  
I need it static because there a instance class that allow me to do that:

```auto
Snake child = new Snake();
child = Population.crossover(father, mother);

```

instead of:

```auto
Snake child = new Snake();
child = father.crossover(mother);

```

It looks more readable because Im god and I play doing crossover, so I made a child using crossover between 2 params! 😃

---

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 7:51pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/11 "2018-08-22T19:51:53Z")

</div>

Now I lost the error cause I got some others in the old files, but It was something related to instance of main class Snakefield correlated to population!

---

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 7:53pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/12 "2018-08-22T19:53:21Z")

</div>

I certainly do!  
I was so tired last night and I create a real no clue post. Sorry, I will do next ones in the right way!

---

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 7:56pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/13 "2018-08-22T19:56:34Z")

</div>

Yeah sure. I fixed the problem but I post it anyway!

```auto
static class Jumble
{
  Snake snakes[]; //All Snakes part of snakes

  int bestScore; //Best score ever achieved
  int bestFitness; //Best fitness ever achieved
  float mutationRate; //Global mutation rate
  int maxPopulation; //Max number of population
  int generation;

  Jumble(float MutationRate, int MaxPopulation)
  {
    mutationRate = MutationRate;
    maxPopulation = MaxPopulation;
    snakes = new Snake[MaxPopulation];
  }

  Jumble(int MaxPopulation)
  {
    snakes = new Snake[MaxPopulation];
    //Be God, create all the Snakes
    for (int i = 0; i < snakes.length; i++)
    {
      snakes[i] = new Snake();
    }
  }

//------------------------------------------------------------------------------------------------------------------

  //Calculates fitness of every snake
  void calcFitness()
  {
    for (int i = 0; i < snakes.length; i++)
    {
      snakes[i].calcFitness();
    }
  }

  //Let's play Noah's Ark
  void naturalSelection()
  {
    Snake[] newGeneration = new Snake[snakes.length]; //next generation of snakes

    for (int i = 0; i < newGeneration.length; i++)
    {      
      //select 2 parents based on fitness
      Snake mother = choseSnake();
      Snake father = choseSnake();
      
      //crossover the 2 snakes to create the child
      Snake child = Population.crossover(motehr, father); //TODO
      //Snake child = parent1.crossover(parent2); //You have could use Instance method of a class
      
      //mutate the child (weird thing to type)
      child.mutate(globalMutationRate);
      //add the child to the next generation
      newGeneration[i] = child;
      
      //newGeneration[i] = selectSnake().clone().mutate(globalMutationRate); //uncomment this line to do natural selection without crossover
    }
  }

  //-----------------------------------------------------------------------------------------------

  Snake choseSnake()
  {
    /*
    This function take all percentage of the snaked and transform into a POOL (array)
    subdivided by the percentage of the snake
    i.e. 
    A=50
    B=30
    C=10
    D=10

    Pool [A|A|A|A|A|B|B|B|C|D];

    Then convert the percentage before insert the snake into array using sigmoid()
    So I get value between 0 and 1 and finally take the best creating new Population
     */
    float[] allFitness = new float[maxPopulation];
    
    //Insert all fitness into array
    for(int i = 0; i < snakes.length; i++)
    {
      allFitness[i] = snakes[i].getFitness();
      //Convert fitness into value between 0<->1
      allFitness[i] *= 100;
      //Make it to percentage
      //NOT SURE TODO, test it until insert fitness!
    }
  }

//-------------------------------------------------------------------------------------------------------

  //Create next Population
  /* void nextGeneration()
  {
    for(int i = 0; i < maxPopulation; i++)
    {
      Snake mother = floor(random())//Fish into the pool
      Snake father = floor(random())//Fish into the pool
      Snake child = Population.crossover(mother, father); //Crossover daddy and mommy
      child.mutate(this.mutationRate);//Mutate the child
      this.snakes[i] = child;//Inser him in the new Jumble
    }
    generation += 1;
  } */
}

```

---

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 7:57pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/14 "2018-08-22T19:57:30Z")

</div>

Thank you for long reply but was my stupid mistake!  
Sorry for your time wasted!

---

<div class="post-metadata">

**Author:** ![neilcsmith](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/neilcsmith/32/144_2.png) [@neilcsmith](https://discourse.processing.org/u/neilcsmith)\
**Post date:** [August 22, 2018, 8:00pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/15 "2018-08-22T20:00:33Z")

</div>

> [@Manatee](#):
>
> It works yes with static and not.  
> I need it static because there a instance class that allow me to do that:

Fair enough. Odd reason! And you shouldn’t need the `Population` field in that case?!

The error message you quoted is caused by trying to reference a non-static inner class from a static nested class - see eg. [java - No enclosing instance is accessible. Must qualify the allocation with an enclosing instance of type (e.g. x.new A() where x is an instance of ) - Stack Overflow](https://stackoverflow.com/questions/47541459/no-enclosing-instance-is-accessible-must-qualify-the-allocation-with-an-enclosi)

---

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 8:06pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/16 "2018-08-22T20:06:15Z")

</div>

Well I definitively have some similar problem now!  
This is the error:

```auto
No enclosing instance of type Main is accessible. Must qualify the allocation with an enclosing instance of type Main (e.g. x.new A() where x is an instance of Main).

```

Here is the class involved:  
Main

```auto

int FPS = 1;//the frame rate
int score = 0;
int bestScore = 0;
int attempts = 1;
int jumbleSize = 200;

Jumble jumble;
Snake snake;

void setup()
{
  //on startup
  size(600, 800);
  frameRate(FPS);      
  snake = new Snake();  
  jumble = new Jumble();// create new population of size 200  
}

void draw()
{
  background(40);
  fill(255);
  stroke(255);
  line(0, 600, 600, 600);
  textSize(30);
  text("Score: " + score, 10, 640);
  text("Length: " + snake.len, 10, 680);
  text("Attempts: " + attempts, 360, 640);
  text("Speed: " + FPS, 360, 680);
  
  textSize(20);
  text("Control Snake using 'wasd'", 100, 725);
  text("Increase/Decrease speed using + or -", 100, 750);
  text("Enable/Disable wall using L " + "(" + snake.getWall() + ")", 100, 775);
  //pos = pos.add(vel);//accelera :D
  //rect(pos.x, pos.y, 10, 10);
  if(snake.getAlive())
  {
    snake.show();
    snake.move();
    // snake.look();//Print what he should see
  }
  else
  {
    redraw();
    snake.reset();
    attempts += 1;        
  } 
}

//---------------------------------------------------------------------------------------------------------------------------------------------------------  

void keyPressed()
{
  switch(key)
  {
  case 'w'://toggle show all  
    snake.turn(1);//Up
    break;
  case 'a'://toggle show all    
    snake.turn(2);//Left
    break;
  case 's'://toggle show all    
    snake.turn(3);//Down
    break;
  case 'd'://toggle show all    
    snake.turn(4);//Right
    break;
  case '+'://speed up frame rate
    FPS += 10;
    frameRate(FPS);
    break;
  case '-'://slow down frame rate
    if (FPS > 10) //Check framerate > 10
    {
      FPS -= 10;
      frameRate(FPS);
    }
    break;
  case 'l':
    snake.triggerWall();
    break;
  case 'c'://Enable cheat, gnam gnam
    //Food food0 = new Food(100, 100);
    //food0.show();
    //Food food1 = new Food(120, 100);
    //food1.show();
    break;
  }  
}

```

Jumble

```auto
static class Jumble
{
  Snake snakes[]; //All Snakes part of snakes

  int bestScore; //Best score ever achieved
  int bestFitness; //Best fitness ever achieved
  float mutationRate; //Global mutation rate
  int maxPopulation; //Max number of population
  int generation;

  Jumble()
  {      
    int bestScore = 0; //Best score ever achieved
    int bestFitness = 0; //Best fitness ever achieved
    float mutationRate = 0; //Global mutation rate
    int maxPopulation = 0; //Max number of population
    int generation = 0;  
  }

  Jumble(float MutationRate, int MaxPopulation)
  {
    mutationRate = MutationRate;
    maxPopulation = MaxPopulation;
    snakes = new Snake[MaxPopulation];
  }

  Jumble(int MaxPopulation)
  {
    snakes = new Snake[MaxPopulation];
    //Be God, create all the Snakes
    for (int i = 0; i < snakes.length; i++)
    {
      snakes[i] = new Snake(); //HERE GET THE ERROR
    }
  }

```

Now I tried put the class Jumble non-static and I have no error, probably I am doing the same thing as last time where @quark and @neilcsmith help me!

---

<div class="post-metadata">

**Author:** ![Manatee](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@Manatee](https://discourse.processing.org/u/Manatee)\
**Post date:** [August 22, 2018, 8:14pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/17 "2018-08-22T20:14:36Z")

</div>

Well u re right!  
I think I have to adapt to don’t have static class and use Random class and avoid instance method… So sad about this, I really like instance methods!

---

<div class="post-metadata">

**Author:** ![EnhancedLoop7](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/enhancedloop7/32/1040_2.png) [@EnhancedLoop7](https://discourse.processing.org/u/EnhancedLoop7)\
**Post date:** [August 22, 2018, 10:32pm UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/18 "2018-08-22T22:32:59Z")

</div>

Oh no it’s not a problem at all, we both made mistakes 😃

EnhancedLoop7

---

<div class="post-metadata">

**Author:** ![quark](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/quark/32/26_2.png) [@quark](https://discourse.processing.org/u/quark)\
**Post date:** [August 23, 2018, 9:44am UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/19 "2018-08-23T09:44:05Z")

</div>

The main problem is that any class defined in the main window is treated as an _Inner Class_, one way to make it a top level class is to declare it as static. This is a **_fudge_** and generally should be avoided.

In Processing the only true way to make a top level class is to declare it in its own .java tab named after the class. For instance your Population class would be in a tab called `Population.java`.

> **IMPORTANT** the tab name must be exactly the same as the class name including case followed by “`.java`” otherwise it won’t work.

Here is a Population class (true top-level class)

```auto
// This is in a tab called 'Population.java'

import processing.core.*;

class Population {
  private PApplet app;
  private int nbrSnakes;
  
  public Population(PApplet papp, int nbrOfSnakes){
    app = papp;
    nbrSnakes = nbrOfSnakes;
  }
  
  public void setNbrSnakes(int nos){
    nbrSnakes = nos;
  }
  
  public int getNbrSnakes(){
    return nbrSnakes;
  }
    
}

```

and in the main tab use this to test it.

```auto
Population p;

void setup(){
  p = new Population(this, 40);
  println(p.getNbrSnakes());
}

```

---

<div class="post-metadata">

**Author:** ![GoToLoop](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/gotoloop/32/86_2.png) [@GoToLoop](https://discourse.processing.org/u/GoToLoop)\
**Post date:** [August 23, 2018, 9:55am UTC](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828/20 "2018-08-23T09:55:03Z")

</div>

> [@quark](#):
>
> **MPORTANT** the tab name must be exactly the same as the class name including case followed by “.java”, otherwise it won’t work.

That’s not necessarily true! As long as a “.java” file doesn’t have any class or interface declared as `public`, it can have any name! 😛

> [@quark](#):
>
> In Processing the only true way to make a top level class is to declare it in its own “.java” tab…

Although true, declaring a nested class as `static` makes it behave pretty much as a top level class as well. 🕶

[Next page](https://discourse.processing.org/t/must-qualify-the-allocation-with/2828.md?page=2)