Line 15 will assign 17 to the static variable x every time a new instance of the class is created. While kind of an odd thing to want to do, it is a logical possibility.
Line 10 does not make sense, the static initializer runs when the class is loaded into memory, an instance does not have to be created and y is an instance variable.
There's a way to do it better - find it. -Edison. A better tiny ad: