Javaweb Study Outline

Java Web Overview

Outline:

1. c/S system structure

2, b/S system organization

3. Comparison of two architectures

4. The main Web application platform

5.java Web Learning Roadmap

1.C/S Architecture

C/S is the abbreviation of Client/server, which is the client/server structure. In this structure, the server usually uses a high-performance PC or workstation, and a large database system (such as Oracle or SQL Server), the client needs to install the dedicated client software, as shown in. This structure can make full use of the advantages of the hardware environment of both ends, and distribute the task reasonably to the clients and services, thus reducing the communication overhead of the system. Before 2000, the C/s structure occupied the mainstream in the Network Program development field.

2, b/s system structure

b/S is the abbreviation of brower/server, ie the browser/server structure. In this structure, the client does not need to develop any user interface, and unified use such as IE and Firefox browser, through a Web browser to send requests to the Web server, processed by the Web server, and the processing results are passed back to the client, as shown in. This structure uses the mature and pervasive browser technology to achieve the original needs of complex special software to achieve the powerful features, thus saving development costs, is a new software architecture. This architecture has become the preferred architecture for today's application software.

3. Comparison of two architectures

System structure	C	b/S
advantages	(1) the interface and operation of the   C/S architecture can be very rich. (2)   security can be easily guaranteed, and it is not difficult to achieve multi-level authentication. The (3) responds faster because there is only one layer of interaction.	1) the client does not need to be installed and has a Web browser. 2) BS architecture can be placed directly on the WAN, through a certain degree of access control to achieve the purpose of multi-client access, interactivity is strong. 3) The BS architecture does not need to upgrade multiple clients to upgrade the server.
Disadvantages	(1) Narrow application surface, usually used in local area network. (2) Fixed user group. Because the program needs to be installed to use, it is not suitable for some unknown users. (3) High maintenance costs, an upgrade occurs, all client programs need to change.	1) on cross-browser, the BS architecture is not satisfactory. 2) It takes a lot of effort to achieve the level of CS program. 3) The high cost of design for speed and security is the biggest problem with the BS architecture. 4) client-side interaction is a request-response pattern and usually requires a refresh of the page, which is not a customer's pleasure to see. (This problem has been eased somewhat after Ajax popularity)

4, the mainstream Web application platform

A dynamic Web server platform must include at least: operating system +web Server + application services + database. A good website server is determined by many factors, such as personal preferences, deployment costs, security mechanisms. And now the mainstream of the three web platforms: ASP, Java and lamp each have advantages and disadvantages.

Three different parts of the platform combination:

ASP.NET:Windows Server+iis+sql server+asp

javaee:unix+tomcat+oracle+jsp

lamp:linux+apache+mysql+php

5.java Web Learning Roadmap

Javaweb Study Outline