UPDATED on March 13, 2017: Add Builder pattern section Most developers have strong opinions regarding whether a language should be strongly-typed or weakly-typed, whatever notions they put behind those terms. Some also actively practice stringly-typed programming - mostly without even being aware of it. It happens when most of attributes and parameters of a codebase are String.

I must confess that despite all benefits of defensive programming, I usually limit myself to not expose mutable attribute to the outside world. Why is that? I believe this is mostly because of readability. Have a look at the following piece of code.