Recommended books before studying the book "Famous Teacher Forum-java development of the actual combat classic"
A prelude to web development
1.1 Web Development
First understand.
1.HTTP: Super Text Transfer Protocol, is a communication protocol.
Through this network protocol WW Browser and WWW server communication between the provisions, and through this protocol we can browse the Web page, through the Web page from the client to write information, from the server to obtain information. The usual HTTP messages include "client-side" and "server-side" messaging, illustrating the capabilities of the HTTP protocol:
is in the client through the browser according to the HTTP protocol to the server side of the request, through the server to the file system to do the corresponding behavior (find the appropriate network files), the server and the HTTP protocol to the client to respond, display in the browser.
2 Fat client and thin client: Whether a separate client program support is required
Because the first use of static web does not achieve a brilliant user experience, so there is an applet program (which is what we call the app), it is based on the Web page of the app. Does not change the server side, just add the dynamic effect on the client. The request and response mechanism (IBID.) is still in use. The FAT client here is that the runtime needs a separate client program (just as you would need to download an app when you're on the Internet).
Applets (small applications written in the Java programming language). )
APP (mobile phone software, is installed on the mobile phone software, improve the original system of deficiencies and personalization. )
3.jvm:java Virtual machine (Java VM)
General high-level languages if you need to configure a certain environment to run on a computer, in order to solve this problem, and we also know that because the Java language is platform-independent, the JVM is running on the actual computer through the virtual machine.
4. Static and dynamic requests
Just as static dynamic, static request is no need to delete and change, need to get the information is built station upload HTML file (HTML is static), and dynamic request is to save the files on the server to make changes. In the initial static web when there is a response to the Web file, you can know that the Web page is actually a separate file.
According to the static request, dynamic request, we can know that static Web pages and dynamic Web pages, the essential difference is whether the database operation.
5.web Container: (a service program that handles requests made from the client)
Web container work involves parsing requests, creating objects, processing requests, creating responses based on request objects, and so on. In fact, we just need to focus on how to connect our program with this black box's thread one by one, the Web container this black box will help us deal with the dynamic request issued. The role of the graphical web container in Dynamic Web pages:
Now look at the Web development process:
Static Web page->applet-> Dynamic Web page
Because static Web pages do not achieve a gorgeous user experience and database operations, there are applets, but because the applet can only achieve a surface experience, can not read and write files, database operations, and must have a separate client (FAT client) these problems persist. The first two are some changes in the client, and there are the above problems, so there is a dynamic Web page. Here are 5 ways to implement Dynamic Web pages: cgi,php,asp,asp.net,jsp.
In the Dynamic Web page, we no longer need the JVM virtual machine, but directly through the browser, the server side has changed, with a Web service plug-in to identify static or dynamic requests, if the dynamic request through the Web container to the dynamic request processing, and then send all the responses to the Web server, The message is answered via HTTP response on the Web browser.
This is the difficult course of the web.
1.2 Enterprise Development Framework
Let's start by figuring out a few concepts.
1.B/S C/S
B/s:browse/server (Browser/service side)
The program schema running on the browser, with the browser as the client, installs the software on the server side, and the user can access the client through the browser.
C/s:client/server (client/server side)
Work software needs to be installed on the local computer, and administrative maintenance needs to be changed on both the client and the service side.
In other words, b/s will be installed in the user computer C/s software installed directly to the service side (the specific difference http://jingyan.baidu.com/article/b0b63dbfc9a2874a483070c0.html)
So, the enterprise Development architecture We are now looking at. If you want to develop dynamic web, through the B/S mode, the different functions of the relevant processing alone, modify the time can also be modified separately, so the modern enterprise we more adopt B/S mode, better division of labor.
Development mode:
JAVA EE is a development platform.
1.3JAVA EE Architecture
Understand the concept.
1.JAVA Se:java Design language and platform of the collective name
Java Se:java Standard Edition, is also the core of Java.
For Java EE, Java SE is equivalent to a syntax rule and is based on Javase. Java EE (Java Enterprise Edition) is a more portable, robust, scalable, and secure server-side Java application.
2.NET Development Architecture: is also a platform development, and is a Java EE-based enterprise development architecture.
What exactly is the JAVA EE architecture? What is it? As you can see from above, JAVA EE is an intermediate for the development platform. The entire Java EE architecture consists of containers, components, and services. Understood to be a specific operation corresponding to a component (the component is the application program, is the app), and the container is equivalent to the black box we say (a container to install a component), I understand the Java EE service is what we see on the platform of the various functions, And these features are Java EE-owned and do not require us to write some of the services of the component container.
And we know that Java EE is used for the development of Enterprise version platform, then it includes three levels to understand the whole enterprise platform development. Customer tier <-> middle tier <-> enterprise Information System layer, different users through the browser or application through the middle layer to get services, and all the data need to be stored in the Enterprise Information System layer.
1.4JAVA EE Core Design pattern
Understand the concept.
1.jsp:java Server Page.
A technical standard for a Web page that enables software developers to dynamically generate HTML, XML, or other format documents in response to client requests. is a dynamic Web technology that combines static technology, such as HTML, with dynamic technology (Java).
2.JAVABean: A reusable component written in the Java language.
To write JavaBean, the class must be public and concrete, with a parameterless constructor. From this place, I understand that the control is equivalent to the call of the function, the controller layer invokes the model component of the model layer, accesses the database in the persistence layer through the model component, obtains some data we reuse through the JavaBean component, and finally displays by the JavaBean and the JSP.
MVC design Pattern: JAVA The most central design pattern in EE is the MVC design pattern. The user requests through the browser, requests back to the control layer to be processed, the result is to call the model layer model component, through the component to the database access, and then save all the results in JavaBean, and finally the JSP and JavaBean to complete the page display.
Schematic MVC design Pattern:
1.5Struts Development Framework
For general projects that do not require so much MVC design patterns, there is a major effect of struts,struts appearing on the development issues on the Web tier.
Learn the first chapter, from the Web development process-Enterprise Development Architecture-java EE Development architecture-java EE Core design pattern: MVC design Pattern-struts Development Framework
Learn about the concepts such as HTTP communication protocol, FAT client with thin client, JVM virtual machine, APPlet, container, etc., with the design of dynamic Web pages complete thinking order, different parts of the technology required, how the different parts relate to each other.
Java Web Development Read the Note: Chapter I.