Class modifiers, member variable modifiers, method modifiers in Java.

Source: Internet
Author: User
Tags modifier modifiers volatile

Class modifier:

Public (access control), which declares a class as a common class, can be accessed by any object, and the main class of a program must be a public class.

Abstract, declaring a class as an abstract class, without implementing a method, requires a subclass to provide a method implementation.

Final, a class life is final (that is, a non-inheriting class), indicating that he cannot be inherited by another class.

Friendly, the default modifier, only objects in the same package can use such a class.

Member Variable modifiers:

Public (Common access control), which specifies that the variable is public and that he can be accessed by any method of the object.

The private access control specifies that the variable allows access only to methods of its own class, and no other methods in any class (including subclasses) are accessible.

Protected (Protect access Control) specifies that the variable can not be accessed by its own classes and subclasses. This variable can be overridden in a subclass.

Friendly, classes in the same package can be accessed, and classes in other packages cannot be accessed.

Final, final modifier, which specifies that the value of this variable cannot be changed.

Static modifier Specifies that the variable is shared by all objects, that is, all instances can use the variable. Variables belong to this class.

Transient (over modifier) specifies that the variable is a temporary variable that is reserved by the system and temporarily has no special effect.

volatile (volatile modifier) specifies that the variable can be controlled and modified by several threads at the same time.

Method Modifiers :

Public (common control character)

Private (proprietary control) specifies that this method can only be accessed by methods such as its own class, which cannot be accessed by other classes (including subclasses)

Protected (Protected access control) specifies that the method can be accessed by its classes and subclasses.

Final, specifies that the method cannot be overloaded.

Static, which specifies a method that can be activated without instantiation.

Synchronize, a synchronous modifier that, in multiple threads, is used to lock the method to which he belongs before running, to prevent access by other threads, and to unlock after the run is finished.

Native, local modifier. The method body that specifies this method is written outside the program in a different language.

Class modifiers, member variable modifiers, method modifiers in Java.

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