Why are static variables considered evil?

Question

I am a Java programmer who is new to the corporate world. Recently I\'ve developed an application using Groovy and Java. All through the code I wrote used quite a good numbe

Answer 1

No. Global states are not evil per se. But we have to see your code to see if you used it properly. It is quite possible that a newbie abuses global states; just like he would abuses every language feature.

Global states are absolute necessity. We cannot avoid global states. We cannot avoid reasoning about global states. - If we care to understand our application semantics.

People who try to get rid of global states for the sake of it, inevitably end up with a much more complex system - and the global states are still there, cleverly/idiotically disguised under many layers of indirections; and we still have to reason about global states, after unwrapping all the indirections.

Like the Spring people who lavishly declare global states in xml and think somehow it's superior.

@Jon Skeet if I create a new instance of an object now you have two things to reason about - the state within the object, and the state of the environment hosting the object.