Q:

Changing value of element in an ArrayDeque

Now I have problem with ArrayDeque specified element. 
Storages.add(new Storage("Furniture storage", 5, 58));

First is storage type. Next one  - floor, and lastone is doorNumber.
Now i want to change specific ArrayDeque element Floor to another one.
For example from second list item 
Meat storage    1   18

to 
Meat storage    7   18      

there is my main class
ArrayDeque<Storage> Storages = new ArrayDeque<Storage>();
Storage storage_obj = new Storage();

Storages.add(new Storage("Furniture storage", 5, 58));
Storages.add(new Storage("Meat storage", 1, 18));
Storages.add(new Storage("Hardware storage", 4, 41));
Storages.add(new Storage("Technique storage", 2, 27));
Storages.add(new Storage("Vegetable storage", 8, 88));

Storages[1] = storage_obj.setFloor(7);

System.out.println("Whole storages list");
outputStorages(Storages);

There is Storage class
    public class Storage {
        private String type;
        private int floor;
        private int doorNumber;

        public Storage(){
            this("------", 0,0);
}
    public Storage(String type_t, int floor_t, int doorNumber_t){
        type = type_t;
        floor = floor_t;
        doorNumber = doorNumber_t;
    }

    void setType(String type){
        this.type = type;
    }
    String getType(){
        return this.type;
    }

    void setFloor(int floor){
        this.floor = floor;
    }
    int getFloor(){
        return this.floor;
    }

    void setDoorNumber(int doorNumber){
        this.doorNumber = doorNumber;
    }
    int getDoorNumber(){
        return this.doorNumber;
    }
}

P.s. Dont judge me for my grammar, English is not my native language^^

A:

There are several issues with your code. I will try to comment them step by step:
ArrayDeque<Storage> Storages = new ArrayDeque<Storage>();

1) Is there any reason, why you are using ArrayDeque? Do you need the double ended queue behavior? Or do you just need a collection? In the latter case, I would suggest to just use ArrayList.
2) The naming convention for the Java programming language specifies to always begin with a lowercase character for variables.
3) It is good practice to use just the interface type for declarations of variables (and also parameters and methods), so you make clear what interface you will use.
To sum it up, I would write:
Collection<Storage> storages = new ArrayList<Storage>();

Next ...
Storages[1] = storage_obj.setFloor(7);

This does not compile. Your Storage class declares a setFloor method with the following signature:
void setFloor(int floor)

That means, your method setFloor does not return anything; thus there is nothing that can be assigned to.
Additionally, the variable Storages is not an array. So you cannot access the first element by using brackets [].
What actually works, is the following code, with which you can alter the first element in the collection:
storages.get(0).setFloor(7);

Note, that I already used the renamed variable.
Something else: Your Storage class declares a parameter-less constructor, which sets some defaults. It's also good practice to enforce users of such classes to pass reasonable values. So I suggest to delete the parameter-less constructor, just leaving the other one, which in turn should do some checks on the incoming arguments (such as checking the type for not being null).

