Manage namespace (Name Spaces)
There can only be a public class in a Java party.
Access control permissions are often referred to as a hidden implementation. To complete the "hidden implementation" while integrating data and methods into classes, completing "hidden implementation". This practice is often referred to as package.
Package is a package that can be accessed each other, and the inherited class can access its public method.
Public any member can be accessed
Private is not accessible unless this class is used. The same package cannot access the Private member.
Class Access Control Permissions: Class Can't be private or protected, you don't want other people to access this class, you can make it constructor
Set to private. In addition to you, no one can create this class object. And you can use the Static method to create this class object. Number
Protected is accessible to the inheritance class, and if you can also access the package member in the same package.
