ch03_layertree question about mastering_openlayers3 HOT 2 CLOSED

Yes, there is. createRegistry is privileged, so it - and only it - can access the protected idCounter variable. idCounter is protected, because the whole layer tree management relies on the uniqueness of layer IDs. This uniqueness is only guaranteed until idCounter is protected. After then, the idCounter will be accessible (rewritable) from outside of the layer tree object, thus it can be compromised (it will be vulnerable).

This can be a real problem, when you aren't the only developer of your code, and one of your colleagues accidentally uses idCounter in a non intended way, breaking the rest of the logic of the layer tree. In another scenario, you finish your code, return to it after a year or two, forget about the unprotected variable, and you use it in a non intended way. This can lead to a debug hell (especially if you don't have unit tests) taking several valuable days out of your hands.

from mastering_openlayers3.

Ok, I see that now. Other than wrapping a prototype.createRegistry in a closure (which would probably be overkill), I haven't found a clean way to move it out of the constructor. It would be nice to have another implementation option here, but the way you did it seems to be the only truly secure way.

Thanks for the feedback.

from mastering_openlayers3.