In Java it seems Public constructors are always a bad coding practice
- by Adam Gent
This maybe a controversial question and may not be suited for this forum (so I will not be insulted if you choose to close this question).
It seems given the current capabilities of Java there is no reason to make constructors public ... ever. Friendly, private, protected are OK but public no.
It seems that its almost always a better idea to provide a public static method for creating objects. Every Java Bean serialization technology (JAXB, Jackson, Spring etc...) can call a protected or private no-arg constructor.
My questions are:
I have never seen this practice decreed or written down anywhere? Maybe Bloch mentions it but I don't own is book.
Is there a use case other than perhaps not being super DRY that I missed?
EDIT: I explain why static methods are better.
.1. For one you get better type inference. For example See Guava's http://code.google.com/p/guava-libraries/wiki/CollectionUtilitiesExplained
.2. As a designer of the class you can later change what is returned with a static method.
.3. Dealing with constructor inheritance is painful especially if you have to pre-calculate something.
