1. Java Interview

1. Why use a single case instead of static

Answer: First you need to understand when static is initialized, what is the design intent, the Singleton is that we run the current virtual machine there is only one required object, there is no duplication. Static static member variables are used for the class, the properties of the class, usually some constants and so on, from the load on the class and objects, when the class is loaded into memory when the statically member variable exists, and the object does not exist, in addition to static methods can only call static methods and static variables, If all the static method, it means that the other members are also static, very inconvenient, if not a single case, it is not easy to expand, and very cumbersome.

1. Java Interview