How to use the Invariant framework in the Java Library to achieve thread security

How to use the Invariant framework in the Java Library to achieve thread security introduction: In concurrent programming, implementation of thread security is very important for the correctness and reliability of the guarantee program.The Java class library provides an Invariant framework to help developers achieve thread security.This article will introduce how to use the constant framework in the Java library to achieve thread security and provide corresponding Java code examples. 1. What is the Invariant framework? Unchanged framework is a design mode for creating thread security categories.Uncosty instances cannot be changed after creation, which means that their state remains unchanged throughout the life cycle.Uncosty is usually used to represent values, such as date, time, currency amount, etc.Some of the basic classes in the Java class library, such as String and Bigdecimal, are typical examples of non -changing categories. 2. Realize the key principles of unchanged categories In order to achieve constant categories, the following principles need to be followed: -Cle the class as FINAL to prevent the inheritance of the subclass. -Plera all fields as Private and FINAL and initialize them in the constructor.In this way, the state of the instance cannot be changed after the creation. -Weoster can provide a method that can modify the class state, but only the access method is provided. -It if the class contains a reference field of variable objects, it is necessary to ensure that it is protected during access or modification to prevent thread security problems. 3. Use the constant framework in the Java library The constant framework in the Java class library provides some classes and auxiliary methods to help developers easier to achieve constant class.Here are some commonly used categories and methods: -FINAL modifier: used to declare classes and fields as non -inheritance and cannot be changed. -PRIVATE and FINAL modifier: It is used to declare the field as private and cannot be changed. -Suchimable collection class: such as ImmutableList, ImmutableSet, and ImmutableMap, etc., used to represent unsatisfactory sets. -Collections.UnmodiFiablexxx () Method: Used to convert variable sets into inseparable sets. 4. Example code The following examples show the constant category of how to use the constant framework to achieve thread security.Assuming we want to create a non -changing Point for two -dimensional coordinate punctuation. public final class Point { private final int x; private final int y; public Point(int x, int y) { this.x = x; this.y = y; } public int getX() { return x; } public int getY() { return y; } public Point move(int dx, int dy) { return new Point(x + dx, y + dy); } } In the above code, the Point class is declared as final to ensure that it cannot be inherited.The X and Y fields are declared as Private and Final, which cannot be modified after initialization.The getX and Gety methods are used to access the values of the field, and the MOVE method returns a new Point object to indicate the movement of the current point relative to the original point. Because the Point class is immutable, multiple threads can access and share the Point instance at the same time without the state of competitive conditions or inconsistencies. 5 Conclusion In concurrent programming, thread security can be achieved by achieving uninvited categories.The constant framework in the Java class library provides simple and powerful tools to help developers create the constant category of thread safety.By following the principle of uninvited categories, the accuracy and reliability of the program can run under multi -threaded environments.