Java access modifiers are used to control the accessibility of members of a class, such as fields, methods, and constructors. There are four access modifiers in Java:

• Public : A public member can be accessed from anywhere in the program.
• Private : A private member can only be accessed from within the class in which it is declared.
• Protected : A protected member can be accessed from within the class in which it is declared, and from within any subclass of that class.
• Default : A default member can be accessed from within the same package as the class in which it is declared.

The default access modifier is not explicitly specified. If no access modifier is specified, then the member has default access.