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1. Singleton mode Introduction Implementation of singleton mode Hungry Chinese style: class loading will cause the single instance object to be created. When a class is loaded, whether it is used or not, the object will be in memory, which will cause a waste of memory. Mode 1: static variable mode package Creator mode.Singleton ...

Singleton mode Ensure that only one instance of an object can exist for a class throughout the software system and that the class only provides a method (static method) to get its object instance. Example: Database client, make sure that only one access class is created for one client access. Hungry Han Style (Static Constant) class Singleto ...

catalogue 1. Structure of singleton mode 2. Implementation of singleton mode 2.1 hungry Han style (static variable mode) 2.2 hungry Chinese style (static code block mode) 2.3. Lazy (thread unsafe) 2.4. Lazy (thread safe) 2.5. Lazy type (double check lock) 2.6. Lazy type (static internal type) 2.7 enumeration method 3. Existing problem ...

Continued from template mode 1 of Glide design mode The list of known implementation classes of LifecycleListener is as follows: AppWidgetTargetBaseTargetBitmapImageViewTargetBitmapThumbnailImageViewTargetCustomTargetCustomViewTargetDrawableImageViewTargetDrawableThumbnailImageViewTargetImageViewTargetNotificationTargetPreloadTargetRequestFut ...

Singleton mode and Volatile learning Beep beep link: https://www.bilibili.com/video/BV15b4y117RJ?p=56 requirement Master the implementation methods of five singleton modesUnderstand why you should use volatile to modify static variables when implementing DCL (double check lock)Understand the scenario of using singleton in jdk 1, Five implem ...

Detailed explanation of design mode - single case mode This article introduces a design pattern - singleton pattern. 　 1, Singleton mode 1. Definitions As the object creation mode, the singleton mode ensures that a class has only one instance, and instantiates itself and provides this instance to the whole system. This class is called ...

Singleton mode 1. Introduction Singleton pattern is one of the simplest forms of design pattern. The purpose of the first mock exam is to make one object of the class a unique instance in the system. To achieve this, you can start by instantiating it from the client. Therefore, we need to use a mechanism that only allows the generation of a uni ...

Shell script operates in the same way as interpretive language. If you have a language foundation, it is very easy to learn shell script. However, shell is different from common languages. Some common functions need to be realized by combining some commands in shell Tool recommendation The Shell does not seem to have a customized IDE. It is r ...

Singleton mode of design mode definition A class has only one instance. The class provides a global access point for external access to the instance. For example, windows can only open one task manager, which can avoid the waste of memory resources caused by opening multiple task manager windows. characteristic A singleton class has on ...

Write in front This exception is not another exception. The exception mentioned in the title is a business exception. Recently, I made a demand for fire equipment inspection. If any abnormality is found in the inspection, submit it through the mobile terminal, and obtain the information and location of the equipment in real time on the backgr ...