Java

1, what is CAsCAS (Compare and Swap), that is, compare and swap. is a mechanism to solve the performance loss caused by the use of locks in multi-threaded parallel situations, theCAS operation consists of three operands-the memory location (V), the

Java constructs BSON data types Integer/Fu Fu pointsJava BSON constructs integer/Fu Fu point types{a:123, B:3.14}bsonobject obj = new Basicbsonobject (); Obj.put ("a", 123); Obj.put ("B", 3.14); StringJava BSON Construct String type{A:

volatile关键字在java并发编程中是经常被用到的，大多数朋友知道它的作用：被volatile修饰的共享变量对各个线程可见，volatile保证变量在各线程中的一致性，因而变量在运算中是线程安全的。但是经过深入研究发现，大致方向是对的 ，但是细节上不是这样。 First, it leads to the effect of volatile.Scenario: When thread a encounters a condition, it wants thread B to

JMX Full name Java Management Extensions, which provides management extensions for Java applications. Introduced in Java 5Concept Name Description Mbean All called managed beans, you can implement an

Collection1. Overview of the collection(1). The reason for the collectionWe are learning object-oriented language, and object-oriented language is the description of things through objects, in order to facilitate the operation of multiple objects,

ObjectiveThe union type and intersection type are all equivalent "types"that combine multiple types, and they are not actual types.Union TypeThe union type is constructed using a bit or operator | :A | B | C Note: the use | of symbols to

In the books I have read, the best of the analysis recursion is the "Mathematics of Programmers" written by the Japanese Chicho.Summarize:HanoiHanoi's Problem?? Now we do not need to know what recursion is, and no need, we first look at a very

The General sort algorithm is a sort of array, and it uses random access methods. However, access to the list is inefficient. In fact, you can use merge sort to sort the list efficiently. The implementation of Java then is to simply transfer all the

FirstSection member Variables1.1member variables and local variablesMember variables: declared under the class, outside of the method, acting on the entire class;Local variables: Declarations are under methods and are used under methods.1.2 member

Project planningFor unified configuration and code decoupling, we have re-organized and planned the code.After re-planning, the code structure is as follows:Kitty-pom: Unified management of Maven versions, packaged configurationsKitty-common: Common

1. Polymorphism : (polymorphism): is characterized by the ability to express various forms; (Professional parlance:) The same implementation interface (reference type), with different instances and different operations

(1) When writing a program, you may need to calculate the square root of a number, the absolute value, get a random number, and so on. The math class in the Java.lang package contains a number of class methods that are used for scientific

Object-Oriented depth1. Object-oriented three major featuresA) Inherit inheritanceSubclasses can inherit properties and methods from the parent classSubclasses can provide their own property methodsb) Package EncapsulationHide some properties and

The garbage collection mechanism (GC) is one of the most important features of Java. It frees developers from the need to focus on the creation and release of memory, but instead automatically reclaims garbage (useless objects) through GC.Which

A callback function, or callback, refers to a piece of executable code that passes through a function parameter to another code. This design allows the underlying code to invoke subroutines defined at the top level.In Java, we use interfaces to

API development often encountered some validation of the request data, at this time if the use of annotations there are two benefits, one is the validation logic and business logic separation, code clear, and the second is the validation logic can

equals method in the object class: Regardless of the new number of objects, when using the"= ="to judge the memory address. If you need to make judgments between objects, you need to override the Equals method: Public BooleanEquals (Object obj)//obj

Package IO;Import Java.io.File;Import java.io.IOException;public class FileIO {/*** Build and get file name information* @param args*/public static void FileName (string[] args) {SYSTEM.OUT.PRINTLN ("Path delimiter:" +file.pathseparator); Path

IntelliJ idea to run your first Java applicationCreate a project let's create a simple Java Hello World project.Click Create a new project.Open the New Project Wizard.The main item you should pay attention to is the SDK. The SDK (software

 1. Semaphore conceptSemaphore is a synchronization tool provided after Java1.5, semaphore can maintain access to its own number of threads and provides a synchronization mechanism. Using semaphore, you can control the number of threads that access