bauhaus design principles

. Until recently, after reading a few books, I found a good way to guide the design of CSS, which is five why or five questions. The five questions came from Toyota's lean production, which was later naturally derived into lean entrepreneurship, and was seen in DDD and UX-related books, with the main thrust of discovering the real reasons behind the massive phenomenon. At first glance it is a management method, in fact I think it is a way of thinking,

structure instead of a doubly linked list. For each database, there is a namespace file that holds the metadata corresponding to each namespace. We can find the storage block location of the corresponding namespace by querying these meta-data. If you turn on the jorunaling log, there will be files that store all of your operational records. 3, storage mmap way to map the file address to the memory address space, directly manipulate the memory address space can manipulate the file, no longer cal

1, in the creation of the data table, for the string type of the field, if the length of the field is clearly known, the char type, otherwise varchar. Char types query faster, but waste storage spaceThe difference between a string char and a varchar is two points: 1, the storage length is different, the char type stores a fixed length, the varchar type is variable length, and a byte is added to the stored content. Like whatCHAR (5) varchar (5)', Memory accounts for 5 bytes ' 1 bytes' Kingwu_han

There is an important concept in the replica set in MongoDB: mostBecause the replica set has only one node that is readable and writable, the other nodes are readable only, and the selection of the master node is determined by the majority, and can continue as the primary node only if support is obtained.(1) Most of the confirmation formula for this number: M=int ((N/2) +1)* Most of the numbers are equal to greater than m, but less than or equal to n;n as the total number of servers in the repli

use an index with a small amount of dataIf the value of the index is long, the speed of the query is affected. For example, full-text retrieval of a field of type char (100) would take more time than a field of type char (10). 6. use prefixes as far as possible to indexIf the value of an indexed field is long, it is best to index it with the prefix of the value. For example, text and blog type fields, full-text retrieval can be a waste of time. If you retrieve only the first few characters of a

I. Design Pattern principles: 1,Single responsibility principle: Specific description: there should be only one reason for a class change, that is, a method should do only one thing as much as possible, that is, to implement only one function as much as possible, and an interface should be responsible for only one class of function description as much as possible, the

: 1. The interface should be as small as possible (core definition ); 2. Interfaces must be highly cohesive; High Cohesion improves the capability of interfaces, classes, and modules and reduces external interactions. 3. Custom Services; Customized services provide excellent services for each individual. 4. Limited interface design; 5. Law of Demeter (dump) is also known as the least knowledge principle LKP) Definition: an object shoul

day good face is also beautiful still need to modify, this time, there is a big kill device appeared-the design is limited, can not indefinitely consider the future change situation, otherwise it will fall into the mire of design can not extricate themselves.Maintain the purity of the interface1, the interface as small as possible, with a single responsibility conflict priority to consider the principle of

language is:1 , the dependencies between the modules can occur through abstraction, and the implementation class cannot have direct dependencies between them, and their dependencies are generated by interfaces or abstract classes;2 , interface, or abstract class does not depend on the implementation class;3 , implementing class-dependent interfaces or abstract classes;a more streamlined definition is "interface-oriented programming" ------OOD one of the essence. Benefits of the dependency inver

corresponding class of methods run at specific times to give advice on what to deal with? ------This requires spring AOP to provide the appropriate advice, which is what we often call advice. End The basic working mechanism of AOP has been introduced, and I stress again that I have simply split the different operating periods of the proxy method into three in order to facilitate understanding of the working mechanism of AOP, and the actual implementation of the AOP proxy i

design "good object-oriented". – Follow certain object-oriented design principles– Familiar with some typical object-oriented design patterns from design principles to design patterns

Accurately speaking, it should be the interaction design principle of the mobile client. I tried to write the interaction design principle one month ago, but I am not talking about it. In terms of mobile phone interaction design, there are very few materials available for reference at home and abroad. You can only use the experience of web pages and software inte

Design principles of design patterns (medium)Interface Segregation Principle, then multiple interfaces are used instead. Each interface serves only one submodule. This is similar to the single responsibility principle shared for the last time. Purpose of designing the interface isolation principle: when designing an application, if a module contains multiple sub-

Reprint Address: http://blog.jobbole.com/685/the following principles, not just software development, can be extended to other production activities, even in our lives .Don ' t Repeat yourself (DRY)Dry is one of the simplest laws and is the easiest to understand. But it can also be the hardest to apply (because to do so, we need to do a lot of work on generic design, which is not an easy task). It means tha

Six main principles:Single duty;Opening and closing principle;Dimitri Principle;The principle of the Richter replacement;dependency inversion principle;Interface Isolation principle23 Different design modes:Create Five types of models: Factory method mode, abstract Factory mode, singleton mode, builder mode, prototype mode. structure mode , a total of seven kinds: Adapter mode, adorner mode, proxy mode, appearance mode, bridging mode, combined mode, e

? In fact, you don't have to worry about where to put it. The dimit rule gives us a solution: If a method is put in this class, that is, the relationship between classes is not added, and there is no negative impact on this class, it is placed in the class. 4. Attention to the dimit rule (iii) -- use serialization with caution Serialization is used to sequence object memory data so that it can be transmitted through different media. However, if our software system model is c/s and the client

should have minimal knowledge of other objects.Scenario: The closer the relationship between classes and classes, the greater the coupling, and the greater the impact on another class when one class changes.The simple understanding is cohesion, a class minimizes dependence on other objects, and the methods and properties of this class can be privatized as far as private. Note:1), only communicate with the direct friends, do not talk with strangers.2), excessive use of the principle, will lead t

This articleArticleYou don't need to understand it once. If you can understand it all at once, I think the design mode is no longer difficult for you .. because the design pattern is to embody these principles, you can regard the design principle as a language, and the design