I understand spring as dependency injection. It can avoid object creating and can directly inject values. But i am comfusing that Dependency injection can not be done without respective classes. Du to this condition, i am comfusing that It reduce dependency of code. Another is that, How injected values are accommodated at memory? for example, statis variables are accommodated in memory when the code start, Reference variables are accommodated when objects are created. By the same way i want to know how spring injected property are accommodated at momory and when time? please answer me.