waterfall model pros and cons

, he may become a car industry experts. But in fact this is rare, and many architects may face another new project, such as you used to make a car, and now you do finance, what do you do. So our general practice is that if a large company, a large team, we will have specialized field experts, by the domain experts to take charge of the business this piece, or by the customer to take charge of the business this piece. But our architects also have to have a certain understanding of the business, a

be initialized3.1 Prototype mode optimizationfunction Person(name) {}Person.prototype = { name: ‘kevin‘, getName: function(){ console.log(this.name) }}var person1 = new Person()Advantages: Better EncapsulationCons: Rewriting the prototype, missing the constructor property3.2 Prototype Mode optimizationfunction Person(name) {}Person.prototype = { constructor: Person, name:‘kevin‘, getName: function() { console.log(this.name) }}var person1 = new Person()

How Ajax works and its pros and cons 1. What is Ajax? Ajax is all called "Asynchronous JavaScript and XML" (Asynchronous JavaScript and XML) and is a web development technique for creating interactive Web applications. It uses: Xhtml+css to standardize rendering, data exchange and related operations using XML and XSLT, asynchronous communication with the Web server using the XMLHttpRequest object, and using

efficiency. NBSP; 2, the connection between the view and the controller is too tight. Views and controllers are separated from each other, but they do have a tight connection, the view has no controller, its application is very limited, and vice versa, which prevents them from being reused independently. NBSP; 3, view low-efficiency access to model data. Depending on the model operator interface, the view

. When NAT is present, the initial design of the TCP/IP protocol process changes and the Internet can become very vulnerable.(3) Nat violates the design principle of the basic network hierarchical structure model. Because in the traditional network hierarchy model, the nth layer cannot modify the header content of the n+1 layer. Nat destroys the principle of independence for each layer.(4) Some applications

performance barriers:2) Session Bean A schema that uses Hibernate to improve the development efficiency of the above architecture:3) Session Bean The above 3 architectures are analyzed:1. Memory consumption: The JDBC Architecture 2 is undoubtedly the most memory-saving, hibernate architecture is the second, EB Architecture 1 is the worst.2, operating efficiency: If JDBC code write is very optimized, then the JDBC schema is the most efficient, but the actual project, this is almost impossible, w

1. Make complex projects easier to maintain by dividing the project into model View and controller.2. The view state and server form controls are not used, which makes it easier to control the behavior of the application3. The application uses a controller to control the request and can provide a rich URL rewrite.4. Better support for unit testing5. Better performance in team development modethe lack of MVC:(1) Increase the complexity of the system st

standards of the Web.5.AJAX points of attention and applicable and non-applicable scenarios(1). Attention PointWhen Ajax is developed, network latency-that is, the interval between a user sending a request to a server to make a response-requires careful consideration. Not giving users a clear response, without proper pre-reading data, or improper handling of XMLHttpRequest, will make users feel delayed, which users do not want to see, but they do not understand. A common solution is to use a vi

1 WebForm Advantages1) Support event Model development, thanks to the rich service-side components, WebForm development can quickly build Web applications2) Easy to use, easier to get started3) Control-rich WebForm2 WebForm Disadvantages1) Encapsulation is too strong, many strata things let us beginners do not quite understand2) Easy to get started, improve hard.3) Complex life cycle models are not easy to learn.4) control is not flexible5) ViewState

of the Web.5.AJAX points of attention and applicable and non-applicable scenarios(1). Attention PointWhen Ajax is developed, network latency-that is, the interval between a user sending a request to a server to make a response-requires careful consideration. Not giving users a clear response, without proper pre-reading data, or improper handling of XMLHttpRequest, will make users feel delayed, which users do not want to see, but they do not understand. A common solution is to use a visual compo

) pros and consThe advantages of the decision tree:The decision tree is easy to understand and explain. People have the ability to understand the meaning of decision trees after they have been explained.Second, for decision trees, the preparation of data is often simple or unnecessary. Other techniques often require that data be generalized first, such as removing extraneous or blank attributes.Third, the ability to handle both data and regular proper

) data name: (NSString ) fileName{NSString *path = [self filepath:filename];[data writeToFile:path atomically:YES];}Get file path+ (nsstring*) FilePath: (nsstring*) FileName {nsarray* mypaths = Nssearchpathfordirectoriesindomains (NSDocumentDirectory, Nsuserdomainmask, YES);nsstring* Mydocpath = [Mypaths objectatindex:0];nsstring* FilePath = [Mydocpath stringbyappendingpathcomponent:filename];return filePath;}Fourth method: Database storageThe library for SQLite is preset in the iOS SDK. Develo

Gossip does not say, we see the title, I use AAAAA and bbbbb two virtual Baidu to promote the account as an example for everyone to analyze the same promotion products of the different two accounts of the pros and cons. Let me first say a current state of the account: AAAAA This account gives the feeling is always very calm, this account of the key words, also on 5,000 words, but this account is still bett

Server: The parallel implementation and coexistence model is immature. It is difficult to handle an increasing number of users and data volumes. Limited scalability. ORACLE: Parallel servers extend the capabilities of WINDOWNT by enabling a set of nodes to share work in the same cluster, providing solutions for high availability and highly scalable clusters. DB2: It has good parallelism. 3. Security SQL Server: No security certificate was obtained. O

developers do not need to consider the logical structure of data, only the business data entities. Hibernate Disadvantages of:1 and inflexible . Since the operations are all objects, it is inconvenient compared to using traditional SQL statements. 3 and achieve complexity . and many complex query SQL statements are difficult to query with hibernate . Therefore, it is difficult for the program to be tuned. 3 , Big Data processing is slow . The transformation of the object

() method, use this directly, you can get the current thread.(2) Cons: Because the thread class has inherited the thread class, it is no longer possible to inherit other parent classes.Implement the Runnable interface method:(1) Advantages: The threading class simply implements the Runable interface and can inherit other classes. In this way, multiple threads can share the same target object, so it is very suitable for multiple identical threads to h

, JasperReports, Tiles, Velocity, and XSLT related classes for internationalization, labeling, Theme, view presentation. Of course, if your application uses a separate MVC framework, no classes in this jar file are required;Spring-webmvc-portlet.jar: Springmvc enhancement, Support Portlet standard (jsr168/jsr286);Via (if shown as initial)Third, the pros and consSpring has a lot of advantages, the benefits of each function module are not the same, such

Comparative analysis of the pros and cons of mainstream PHP frameworks, comparative analysis of framework advantages and disadvantages PHP is a popular open source server-side scripting development language both at home and abroad. Able to adapt to the development needs of large and medium-sized projects. In this article we will introduce several mainstream PHP framework and its related advantages and disa

of mobile terminal (voice, camera, SMS, GPS, Bluetooth, gravity sensor, etc.)(5) The app updates new features that involve submitting audits to each store every time.Suitable for enterprises: games, E-magazines, management applications, the Internet of things, etc. without the need to constantly update the application framework of the app.Mobile Web is ubiquitous, mobile web is currently the only platform to support a variety of device access, like the desktop web, mobile Web support a variety

developed, network latency-that is, the interval between a user sending a request to a server to make a response-requires careful consideration. Not giving users a clear response, without proper pre-reading data, or improper handling of XMLHttpRequest, will make users feel delayed, which users do not want to see, but they do not understand. A common solution is to use a visual component to tell the user that the system is in the background and is reading data and content.(2). Ajax Application S