Writing to a static variable in an instance method, why is this a bad practice?

Question

I am a little confused here with this findbugs warning in eclipse.

public class MyClass {
    public static String myString;
}


public class AnotherClass {         


        

Answer 1

This is my take, so take it with a grain of salt. You mentioned synchronization issues, which are a major reason for this warning, but more importantly, the two cases are fundamentally operating on different conceptual "levels" of data. Instance methods are "owned" by objects and modify data that describes individual instances. Class methods are generic operations and state that, while related to the class, are not related to individual objects. Thus, modifying that state from within each instance would probably (but not necessarily) be a poor design decision.