src/main/java/com/workplacesystems/utilsj/collections/HashMap2Template.java
public V getOrCreate(K1 key1, K2 key2)
    {
        // already got it?
        if (containsKey(key1,key2))
            return get(key1,key2);
        
        // if not, create and add it
        V result = create(key1,key2);
        put(key1,key2,result);
        return result;
    }
public V getOrCreate(K1 key1, K2 key2)
    {
        // already got it?
        if (containsKey(key1,key2))
            return get(key1,key2);
        
        // if not, create and add it
        V result = create(key1,key2);
        put(key1,key2,result);
        return result;
    }
Method to get existing [key1,key2] value or create new one if it's absent.
Needs implementation of create(key1,key2) in order to work