Global variability, and single-instance mode and multiple-instance mode parsing

1. There is no global variability in Java because the variables are encapsulated within the scope of the category. The communication between classes is through the inheritance or the actual interface and the injection dependency (combination) system.

a) in the concept of orientation-oriented programming, we usually refer to the variables in the category as global variables, and the variables and function parameters in the subroutines of the class are called local variables.

b) The amount of static change in a category is the life cycle that changes the variable, and the life cycle of the static change is the same as the life cycle of the species .

c) the role of accessibility in a category is to change the scope of the variable, and only the change of public decoration or the method subroutine can be used in an external file.

d) the variation of the protected or the scope of the subroutine is the extension of all subclasses of that category, and the function of the private rights modifier is to limit the scope of the variables to the scope of the category, and the external file is a non-private variable.

e) So, in orientation-oriented programming, we can change the amount of public static final trim and the global variables in C + +. The variation of the public trim or the scope of the subroutine can span multiple files, which is the overall name. When in a category, all variables that are outside of the method's stay can be called global variables. The above concept is only a description of whether the variables are global in different situations when the program is programmed.

f) scope of local variables and global variables:

I.

2. diagram of the single-mode and multiple-case modes:

Global variability, and single-instance mode and multiple-instance mode parsing