hungry buzzard

solved by using volatile at this time. PackageSingleton; Public classSingleton3 {PrivateSingleton3 () {}//private only intrinsic functions can be called Private volatile StaticSingleton3 instance =NULL; Public Static synchronizedSingleton3 getinstance () {//sync Lock To resolve thread synchronization issues if(Instance = =NULL) {//lock time, reduce the number of locks synchronized(Singleton3.class){ if(Instance = =NULL) {instance=NewSingleton3 ();//construct

negative problems, such as a singleton class designed to conserve resources for the database connection pool object, which could result in a connection pool overflow for programs that share connection pool objects, and if the instantiated objects are not exploited for a long time, the system is considered garbage and is recycled, which results in the loss of the object state.Common Application Scenarios:The class of the read configuration file commonly used in code, we will only have one object

A proxy is a simple and powerful design pattern that is used by an object to "represent" another object to do and implement something. The main object maintains a reference to a proxy (delegate) and sends a message to the agent at the appropriate time, which notifies the "agent" that the object is about to be processed or that an event has been processed. The agent can respond to the message of the event sent by the main object by updating the UI interface or other state of the object. Or, in so

This is a good example to help you understand the event mechanism. Using system; Namespace vczx. procsharp. Event{/// /// Class eateventargs must inherit from class eventargs to encapsulate data when an event is triggered./// Public class eateventargs: eventargs{Public String restrauntname; // hotel namePublic decimal moneyout; // prepare the consumption amount} /// /// This delegate is used to describe the method header (mode) for processing meal events)/// Public Delegate void eateventha

We all know how a simple singleton pattern should be implemented: the constructor is declared as private or protect to prevent being instantiated by an external function, and a private static class pointer is stored inside a unique instance, and the action of the instance is handled by a public class method. The method also returns an instance of the Singleton class. There are about two implementations of the Singleton: The lazy and the A hungry man.L

snoring is also very level, strange ring. 　　 1:30 very hungry, want to eat something. 　　 1:33 to find a half-day or not eat, get out of bed and drank half a cup of cold water. 　　 1:36 recall some of the beauties met during the day. 　　 1:37 more hungry. 　　 1:39 comfort himself will soon be hungry, as if not halfway. 　　 1:47 seems to have the trend of

a girlfriend.Then we'll be in the client new one.publicclass Client { publicstaticvoidmain(String[] args) { new GirlFriend(); }}problemLet's just try to imagine. Suppose we are in the client, and then to "find" a girlfriend, is not also able to.publicclass Client { publicstaticvoidmain(String[] args) { new GirlFriend(); new GirlFriend(); System.out.println(gf==gf1); }}And. The code above. Finally the result is also false.That, as a principled man, is not

Concept: 　　 In Java, the singleton pattern is a common design pattern, and the singleton pattern is divided into three kinds: lazy type single case, a hungry man type single case, registration type single case three kinds.There are a few features of the Singleton model: 　　 1, the Singleton class can have only one instance.　　2. The Singleton class must create its own unique instance itself.　　3. The Singleton class must provide this instance to all othe

The single case (Singleton) pattern in Java is a widely used design pattern. The primary role of a singleton pattern is to ensure that only one instance of a class exists in a Java program. Some managers and controllers are often designed as a single case pattern. The singleton pattern has many advantages, it avoids the duplication of instance objects, reduces the time cost of creating objects, saves memory space, and avoids logic errors caused by manipulating multiple instances. If an object ha

, "Confucius spent 55 years of time. As a programmer, you need to constantly enrich your knowledge base. What we know, like a white circle, outside the circle is the dark unknown world. The larger the circle, the more dark parts it touches. We can only break more darkness and find more light if we keep on learning. Keep hungry and stay stupid I like the words of jobs very much: "If you are hungry, if you ar

moments, "Confucius spent 55 years of time. As a programmer, you need to constantly enrich your knowledge base. What we know, like a white circle, outside the circle is the dark unknown world. The larger the circle, the more dark parts it touches. We can only break more darkness and find more light if we keep on learning. Keep hungry and stay stupid I like the words of jobs very much: "If you are hungry, i

knowledge. What we know, like a white circle, outside the circle is the dark unknown world. The larger the circle, the more dark parts it touches. We have to learn, to break more darkness, to find more light. (3) to remain hungry, to remain stupid: "If you are hungry, if you are ignorant" (Stay hungry,stay Foolish), the original translation of the ecological "ke

mode can be applied under the following conditions: when the class has only one instance and the customer can access it from a well-known access point; When this unique instance should be extensible by subclasses, and the customer should be able to apply an extended instance without changing the code. the design method of single case model The singleton pattern requires that the constructor of the class be private , that is, the private modifier, to ensure that the object of this class cannot

as soon as it is loaded. The other is described below: class single{ private single () {} private static single s = null ; public static void getinstance () { if (s = = Span style= "color: #0000ff;" >null ) {s = new single (); return S; } } }The above form is the object that is created when the method is called. Also known as deferred load form.In order to distinguish between two forms: the first is called a Hungry