ruby singleton

In Singleton mode, the most important concern is the number of object creation times and the time when the object was created. The Singleton mode can be very simple, and only one class is needed to complete it (look at the poor UML diagram in this chapter ). HoweverThe Singleton mode can be quite complex than the first five modes, for example, involving the DCl d

Based on Singleton in the design mode, JS implements the function of adding, deleting, modifying, and querying data by encapsulation. The design mode is singleton. This article describes how to add, delete, modify, and query data by using the Singleton mode in the design mode of JS. We will share this with you for your reference. The details are as follows:

Singleton mode is the simplest and most understandable pattern in the development model. To put it simply, it means to always keep an instance of the meaning. However, the Java class can wear a number of instances, then, how to implement it?As the name implies, Singleton mode is just one instance. The singleton pattern ensures that there is only one instance of a

Example of an interactive program developed by ruby: ruby Development Implement the interaction function in a terminal similar to pry, ronin, and msf. ripl gem is mainly used here: 1. Call defined methods, such as help2. Be able to execute system commands3. ruby parsing similar to irb/pry Installation: gem install riplgem install ripl-shell_commands Example Ripl,

Overview The Singleton mode requires that a class has only one instance and provides a global access point. This raises a question: how to bypass the conventional constructor and provide a mechanism to ensure that a class has only one instance? When a customer program calls a class, it does not consider whether the class can only have one instance or other issues, Therefore, this should be the responsibility of the class designer, not the responsibili

Design Patterns ----------- Singleton design patterns, Singleton Design PatternsHungry Chinese Style: class Single {// do it in advance! Private static final Single s = new Single (); // private constructor cannot use new to create an object! Private Single () {}// public static Single getInstance () {return s ;}}Lazy style: As the name implies, lazy guy is lazy. When will it be used to create it!Class Sing

Reference: HTTP://BLOG.CSDN.NET/LOVEFQING/ARTICLE/DETAILS/8516536#T3http://blog.csdn.net/kindazrael/article/details/7917863The singleton pattern is used when a class can have only one instance, typically this "singleton " represents a physical device such as a printer, or some kind of virtual resource or system attribute, such as a program's engine or data, that can not have multiple instances at the same t

GitHub advocates a summary of Ruby coding styles, while github advocates ruby code. Source code layout: 1. All source files are UTF-8 encoded2. indent with two spaces3. Use Unix-style line breaks (\ n) and windows (\ r \ n ). You can use git config -- global core. autocrlf true to prevent the generation of windows-style line breaks.4. After ',', ';', add spaces before and after the operator (except for expo

The singleton (singleton) pattern is known because it restricts the instantiation of a class to only one time, and in the case of a singleton pattern, a class can be created with a method to create a new instance of the class, and if the instance already exists, a reference to that object is simply returned. Singleton

How to implement Singleton (Singleton mode) Singleton mode in PHP has the following features :? A singleton class can have only one instance. The singleton class must create its own unique instance. The singleton class must provid

C ++ Primer study note _ 24 _ class and data abstraction (10) -- static and Singleton modes, auto_ptr and Singleton modes, const member functions, const objects, mutable modifiers, constmutable C ++ Primer study note _ 24 _ class and data abstraction (10) -- static and Singleton modes, auto_ptr and Singleton modes, con

Single-Case modeThe core structure of the singleton pattern contains only one special class that is called a singleton. The singleton mode ensures that there is only one instance of a class in the system.The initial definition of the singleton pattern appears in design mode (Eddisonvis, 1994): "Guarantees that a class

What is the PHP Singleton mode? This article mainly introduces how to implement the singleton mode in php and tells you why the singleton mode is used. If you are interested, refer 1. What is Singleton mode? 1. MeaningAs the object creation mode, the singleton mode ensures t

JAVA design patterns-Singleton and singletonReprinted please indicate the source: http://blog.csdn.net/l1028386804/article/details/45441169I,Overview Ensure that a class has only one instance and provides a global access point to it.II, Applicability 1. When the class can only have one instance and the customer can access it from a well-known access point. 2. When this unique instance should be extensible through subclass, and the customer should be a

Detailed explanation of the iterator IN Ruby and the Ruby Generator D guago recently wanted to build a website. In addition, he had long had the idea of learning a dynamic language. Among the programming languages that meet two conditions, Ruby and Python are the most appropriate. Now Ruby on Rails is booming! Therefor

Understand Ruby scopes and Ruby scopes What is scope? When talking about the scope, you should immediately thinkVariableAndVisibilityThese two words,VariableAndVisibilityIt is the main content of the scope. Yes, the scope is about where the code variables are visible. After you fully understand the scope, I will give you a piece of code, you can easily know what variables are visible at this time, and most

Definition of a singleton pattern: guarantees that a class has only one instance and provides a global access point to access it. Singleton mode is a common pattern, and there are some objects that we often only need one, such as a thread pool, a global cache, a browser window object. In JS Development, the use of singleton patterns is also very extensive. Imagin

How to learn Ruby? What do you need to know before you learn Ruby? This is a lot of people want to learn the voice of Ruby friends, I do not give a specific answer, the following to tell you about a predecessor learning Ruby (http://www.maiziedu.com/course/ruby/) learning pr

Gems use proxies in two ways: Mode one: >>set http_proxy=http://ip_or_host:port >>gem Install The_package_name Mode two: >>gem list-p Http://user:passwd@ip_or_host:8080-r Install Ruby-debug-base19There are 2 different ways:Method One:download the. gem file first, then install the. gem file directly, which requires compilation, so you need to take the With-ruby-in

The concept of class objects in Ruby and the concept of ruby objects Object-oriented Programs involve classes and objects. A class is a blueprint created from an individual object. In object-oriented terms, we say that James's bicycle is an object instance called a bicycle. Example of any vehicle. It includes wheel, horsepower, fuel or gas tank capacity. Data members of vehicles with these features. These f