java learning day9

When a parameter is passed by a reference data type, the memory address is passed. When the called method performs an operation on the parameter,

The memory address has changed, and the value of the passed parameter will also change

Basic data types will not be
private 
default. In the current package, you can access
protected. The parent-child relationship of the package has
the most public permissions, and anyone can access it. As long as it is in the current project,
method overloading has
the same name and different
parameters . There can be multiple methods with the same name in the same class. methods, as long as they differ in the number or types of parameters