Get all possible combinations of child records

Question

I have a Parent Object let's call it X__c and I have 4 child objects Ax__c, Bc__c, Cc__c, Dc__c I'm trying to create a List of Wrapper class out of the following data structure:

The above data structure would be saved in the following collections:

Map<X__c, List<Ax__c>>
Map<X__c, List<Bc__c>>
Map<X__c, List<Cc__c>>
Map<X__c, List<Dc__c>>

Wrapper Class:

public wrapclass {
    X__c parent;
    Ax__c childA;
    Bc__c childB;
    Cc__c childC;
    Dc__c childD;
}

I want to save all the combinations of all the child records related to the same parent record in a List<wrapclass>

So at the end of it I want my List<wrapclass> to look like this:

        wrapclasslist = [
    {
        parent = X__c,
        childA = Ax__c -1,
        childB = Bx__c - 2
    },
    {
        parent = X__c,
        childA = Ax__c -2,
        childB = Bx__c - 2
    },
    {
        parent = X__c,
        childA = Ax__c -2,
        childB = Bx__c - 1
    },
    {
        parent = X__c,
        childA = Ax__c -1,
        childB = Bx__c - 1
    }
];

I know this can be done using nested for loops but, I'm looking for a more optimized solution. Any help is appreciated

Answer 1

Design your wrapper class as

public wrapclass {
    X__c parent;
    List<Ax__c> childAList;
    List<Bc__c> childBList;
    List<Cc__c> childCList;
    List<Dc__c> childDList;
}

So Here you will tag multiple child records with same parent and can use simple nested for loop to iterate and get value from them.