design patterns explained simply

Design in design mode, Factory method is also a relatively simple one, but the application is very broad, ejb,rmi,com,corba,swing can see the shadow of this pattern, It is one of the most important patterns. In many places we see xxxfactory classes like this, so what is factory method, why use this pattern, how to use the Java language to implement the pattern, t

singletonholder.instance, causing the Singletonholder class to be initialized, and when the class is loaded and initialized, it initializes its static domain to create an instance of singleton, because it is a static domain, so only when the virtual machine loads the class Initialized once and is guaranteed to be thread-safe by a virtual machine.The advantage of this pattern is that the GetInstance method is not synchronized and only performs a domain access, so deferred initialization does not

operation of this class. The related conditional branches are moved into their respective strategy classes in place of these conditional statements. Visitor (visitor) Intention: Defines the skeleton of an algorithm in an operation, and delays some steps into subclasses. Templatemethod allows subclasses to redefine some specific steps of the algorithm without altering the structure of an algorithm. Applicability: One-time implement

The Observer pattern is one of the software design patterns, and is more common, especially in GUI programming. On the design model of the article, the network wrote more, and a lot of writing is good, although there is a repetition of the early wheel of suspicion, but this wheel is not that wheel, the focus is different, the idea is different, the way is not nea

all the existing modules are abstracted, but there are some subtle differences. What the mediator does is to communicate between modules, but the appearance pattern simply defines a simple interface for a module or system without adding additional functionality. The concept of other modules and appearance patterns in the system is not directly related, and can be considered one-way. A complete example is

immediately is a process-oriented development route, using the software development model of side-by-side modification (Build and Fix model).Remember, any change in requirements, the expansion of functionality is a cost.Reference: Architecture Ramble (ix): clarify the relationship between technology, business and architecture http://kb.cnblogs.com/page/543110/ All design patterns are designed to faci

Design patterns:solidify Your C # application architecture with design Patterns Chinese version (tail article i) optimizer (translation) Keyword design pattern singleton strategy Decorator Composite State SOURCE http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnmag01/html/PATTERNS.asp

Design Patterns Learning Notes-Memo (Memento) mode @ (design mode) [design mode, Memo mode, Memento] Design Patterns Learning Notes Memo Memento Mode Basic Introduction Memo case class diagram implementation code Memento Class ga

, do not need to create factory objects, this pattern is more extensive, the code example is as follows: Package Com.factory.factorymethod;public class Senderfactory {public static sendable Producetextsender () { return New Textsender (); } public static sendable Producephotosender () { return to new Photosender ();} public static sendable Producevideosender ( { return new Videosender ();} } Factory Method Model Summary When there are a large number of products that need to be created and

Gossip not much to say, today to talk about decorator mode: First of all, I think to learn design patterns, remember that its definition is really important, or at the beginning you do not understand, but after understanding the connotation of the pattern, you will find the definition of incisive. Decorator Mode: Dynamically attaches responsibility to objects, and to extend functionality, adorners provide a

Iterator mode:Provides a way to sequentially access individual elements of an aggregated object without exposing the object's internal representation. Leveldb Include/leveldb.h defines the iterator base class, which accesses a layer of SST, a SST internal kv, a memtable internal kv, and the entire DB internal KV requires an iterator. is to implement its own version of the iterator by inheriting iterator. This separates the functions that traverse data in a container from other functions, adheres

Group Creation Intention I was reading refactoring to patterns during the Qingming Festival holiday in April 6, 2013. The book mentioned that Joshua kerievsky created the "New York City Design Patterns Learning Group" in New York as early as 1995 ", study a design pattern through peer programming at weekly meetings. T

"); }}///////////////////////////////////////////////////////////////////////////////////Public interface Factoryinterface { public Studentinterface createstudent ();}public class Factorystudenta implements factoryinterface{ @Override public Studentinterface createstudent () { //TODO auto-generated method stub return new Studenta (); }}public class FACTORYSTUDENTB implements factoryinterface{ @Override public Studentinterface createstudent () { //TODO auto-generated method stub return new STUDEN

: Http://book.cnblogs.com/zt/DesignPatterns/ Then select related topics. -Purpose This is an example of the book "design patterns-engineering implementation and expansion based on C #" for readers to refer to and learn when reading books. Ii. Content Contains all examples of this bookSource code Sample source in this bookCodeSave by chapter, including 40 chapter examples. Iii. Runtime Environ

there is no abstraction layer in the singleton pattern, the expansion of the Singleton class is very difficult.(2) The duty of the Singleton class is too heavy, which violates the "single duty principle" to a certain extent. Because the Singleton class serves both as a factory role, provides a factory approach, and acts as aProduct roles, including business methods, combine the creation of products with the functionality of the product itself.(3) Many object-oriented languages (such as Java, C

implementation. Because the structure inside the parameters are eat interface, as long as the implementation of the Eat class can be passed in, that is to show　　　　　　　　　　Likeeat likeeat = new Endeat (New Eatfoot (New Inrestaurant (New Gotorestaurant (New Findinmap (person)))))The look of this structure. So when calling Likeeat.eat () , and because of each specific decorator class, first call super.eat (); method, and the Super has been passed by the construction and pointed to a specific decorat

JAVA design patterns ---------- Proxy) Here is a brief introduction to the use of the most basic proxy. Agency: Simply put, one person or one institution takes action on behalf of another person or another institution. In some cases, a customer does not want or cannot directly reference an object, but the proxy object can play a mediation role before the client a

systems with relatively undetermined data structures. It frees the coupling between the data structure and the operations acting on the structure, allowing the operation set to evolve freely. The visitor mode makes it easy to add new operations, that is, to add a new visitor class. In the visitor mode, the related behaviors are concentrated in a visitor object, rather than scattered into node classes. When using the visitor mode, put as many object browsing logic as possible in the visitor clas

Createproduct method under Simplefactory.Factory methodIt can be seen that unlike a simple factory, each of our FactoryMethod implementation classes only produces a single product, that is, this is the generation of fixed products.For adding new products, we simply implement the product interface and create a new FactoryMethod implementation class to help us create the product without needing to modify other code.Abstract FactoryFor abstract factorie

(! $value->update ($this)) {return false;}} return true;} Public Function Addpost () {if (! $this->notify ()) {return false;} // ... }} Quite simply, the most important thing is to understand that in this example, we have stripped away some of the auditing methods from the Post class, and the Post object can be used as another release type. The above content implementation is small to introduce you to the PHP de