What technical requirements are required for Java Web Development (simple Web Interface Management system)

At present, the information construction at home and abroad has entered the stage based on Web application, Java as the best language to be used in the network, the foreground is optimistic. However, it is not easy to build a Web application that is not trivial, even in Java. To summarize, the techniques for implementing a Java Web project are as follows:

Ljava language

L Object-oriented analysis design idea

L design pattern and frame structure

lxml language

L Web scripting language

L Database

L Application Server

L Integrated Development Environment

Let's look at each technology in detail below.

1. Java language

The Java language system is quite large, including multiple modules. From the perspective of Web project application, JSP, Servlet, JDBC, J

Avabean (application) four-part technology.

(1), Java Database Connectivity (JDBC) technology

In Java Web application development, the use of database management system (RDBMS) is indispensable. JDBC (Java Dat

Abase Connectivity) is a Java API for executing SQL statements. It consists of a set of Java programming languages

The classes and interfaces that are written in the word. JDBC provides a standard API for tool/database developers to enable them to

Write database applications with pure Java APIs.

To put it simply, JDBC can do three things:

l Establish a connection with the database,

L Send SQL statements,

L PROCESS the results.

(2), servlet technology

Servlets are programs that run on the server side and can be considered server-side applets. Servlet is Web server

(such as Tomcat) are loaded and executed just as applets are loaded and executed by the browser. Servlets from the client (

Receives the request through a Web server, performs some action, and then returns the result.

The main benefits of Servlets include

The Lservlet is persistent. The servlet only needs to be loaded once by the Web server, and it can maintain service between different requests

(for example, a database connection).

Lservlet is platform-independent. As mentioned earlier, the servlet is written in Java and naturally inherits Java's flat

independent of the station.

The Lservlet is extensible. Since the servlet is written in Java, it has all the advantages that Java can bring

。 Java is a robust, object-oriented programming language that can easily be scaled to suit your needs. The servlet naturally has

These features are prepared.

The Lservlet is safe. The only way to invoke a servlet from outside is through a Web server. This provides a high

Level of security, especially when your Web server has firewall protection.

Lservlet can be used on a wide variety of client computers. Since the servlet is written in Java, you can

To use them in HTML.

(3), JavaServer Pages (JSP) technology

JSP is a small part of the servlet, which simplifies the development and strengthens the interface design. JSP positioning in the interactive network

Development of the page. Java syntax is used, but the functionality is much weaker than the servlet, and the advanced development only serves as the user interface department

Score of When a JSP container receives a request from a client, it first executes the program fragment and then executes the result in an HTM

The L format responds to the client. Where the program fragment can be: manipulate the database, redirect the Web page, and send e-mail

And so on, these are the functions needed to build a dynamic website. All program operations are performed on the server side, network uploads

The only results that are given to the client are not related to the client's browser, so the JSP is called Server-side La

Nguage.

Key benefits of JavaServer pages include

Write once, execute everywhere (write o­nce, Run Anywhere) features

As part of the Java platform, JavaServer Pages technology has the Java language "write once, execute everywhere"

The characteristics. As more and more suppliers add JavaServer Pages technology to their products, you can pin

After careful evaluation of your company's needs, choose a server that meets the company's cost and size, if future needs

Change the server platform does not affect the cost of the previous investment, the human development of the application.

Paired with reusable components

JavaServer pages technology can rely on reusing cross-platform components such as: JavaBean or Enterprise Jav

Abean components) to perform more complex operations and data processing. Developers can share development-completed components, or they can

To enhance the functionality of these components so that more users or customer groups are used. Based on the method of good use of components, you can

Accelerate the overall development process, but also greatly reduce the company's development costs and manpower.

Developing with tabbed pages

Web page developers are not necessarily programmers who are familiar with the Java language. As a result, JSP technology can seal many functions

Installed to become a custom label, these features are entirely based on XML standards, that is, JSP technology

Tag Library. As a result, Web page developers can use custom tags to achieve work

requirements, without having to write complex Java syntax, so that Web page developers can quickly develop a dynamic content page

。

In the future, third-party developers and other people can create their own tag libraries for common functions, allowing web page developers

Can use familiar development tools, like HTML-like tag syntax, to perform specific functions.

N-tier Support for enterprise application architectures

In view of the development of the Internet, in response to the increasingly complex requirements of future services, and no longer subject to geographical constraints, so

，

The two-tier architecture of the past Client-server must be abandoned, thus turning to a more powerful and resilient dispersion object system.

Ec Because JavaServer Page technology is a Java 2 Platform Enterprise Edition (ee) integration

Part, it is mainly responsible for the front end display after the complex operation of the result content, and the decentralized object system is the main

To rely on EJB (Enterprise JavaBean) and Jndi (Java naming and Directory Interface

) built.

(4), JavaBean (application) Application component Technology

Application is a Java application that primarily applies javabean in Web projects and some development. It's applic.

Ation is a part of the logical computing ability is very strong, can greatly exert the advantages of the Java language. JavaBean is known to be

The core of Java component technology. The structure of the JavaBean must meet certain naming conventions. JavaBean can provide common

Functionality and can be reused, which allows developers to extract certain key functions and core algorithms to encapsulate

As a Component object, which increases the reuse rate of code and the security of the system.

Advanced Web projects are applied to all of these technologies, and joint use and collaborative development between them will improve the efficiency of development and

Performance of the system.

2. Object-oriented analysis and design ideas

The Java language is a fully object-oriented language, so it can be very helpful in project design and should be designed with as much

Abandon the previous process-oriented design approach.

When analyzing the project business relationship, apply some UML (Unified Modeling Language) diagrams, such as the common

Example diagram (use case diagram), Class diagram (class diagram), timing diagram (sequence diagram), etc., there will be

A lot of help, so as soon as possible to identify the main business logic of the object, and then the behavior of each object to divide,

Finally, the integration and communication between objects are realized.

3. Design pattern and frame structure

Java is not very difficult in terms of language, but we need to know some advanced application boxes from a holistic design perspective

Rack Mastering the Java language alone is not enough if you want to design a good frame structure. This involves a set of

And some knowledge related to design patterns.

Design Patterns in the Java project implementation process is the most serious. Mainly in the design mode with two-layer, three-layer design mode

and n-tier design patterns. It directly determines the application, deployment and actual development design of the project.

Many of the common Web projects use two-tier development constructs. Jsp+servlet or Jsp+javabean. When the development to be

The high-level project uses a lot of MVC's three-tier development structure, also known as Jsp+servlet+javabean. It can be divided into

Effective separation logic development enables developers to focus on their own development. At the same time, the entire development structure process can be

Clear, but requires a relatively high degree of development coordination.

In the project, we often use the well-known model-view-controller (MVC) architecture. The MVC architecture is with small

Talk language the development of language, it is a well-known user interface design architecture. The Classic MVC architecture

A component (which can be thought of as a module of the entire application) is divided into three parts of the Model Management module

The data and business logic used. And how the View management module is displayed to the user, the Controller decides what to do with

When the user clicks on a button, and so on, when the module interactively generates events.

4. XML language

The customization file is applied to the server and design pattern structure, and when you apply the advanced design, you also define your own

tags, now the popular is to use XML to define the configuration, so the XML language should have a certain grasp.

Currently, the Java 2 Platform Enterprise Edition (EE) architecture is highly regarded in the vendor market and the developer community. As a work

Extensible Markup Language (XML) simplifies data exchange, inter-process message exchange, and thus the development

Gradually became attractive and began to pop up. Naturally, the need to access or integrate XML solutions in the Java EE architecture

Law is also very tempting. This will be a combination of a powerful system architecture and a highly flexible data management solution.

XML applications seem to be endless, but they can be broadly divided into three broad categories:

1. Representation and exchange of simple data (Simple API (SAX) for XML and Document Object Model (DOM) syntax parsing,

Different document type definitions (DTDs) and summaries (schemas))

2. User interface related, presentation related context (Extensible Stylesheet Language (XSL), Extensible Stylesheet Language goto

Change (XSLT))

3. Message-Oriented computing (XML-RPC (remote Procedure Call), SOAP protocol-based Web service (Web Servic

ES), E-business XML (EbXML))

5. Web scripting language

In order to improve the overall performance of Web projects, improve the user-friendly interface of human-computer Interaction, Web page scripting language is very useful,

Sometimes it can solve big problems or improve the performance and application of the program.

The execution of the Web scripting language is performed on the client, very quickly, and most of the operations are not delivered to the server.

Interoperability, so it is ideal in some applications. In the application of designing Web projects, the scripting language of Web pages does not

Ignore the role, so if you design Web project applications, JavaScript should have some understanding.

JavaScript is an object-based (Based) and event-driven (driven) and has security performance (

Secure) scripting language. It is intended to be used with HTML Hypertext Markup Language, Java scripting language (Java thread

To link multiple objects in a single Web page, interacting with web customers. So that you can develop clients

Applications, and so on. It is implemented in the standard HTML language by embedding or inserting. It has the following basic special

Point:

1. It is a scripting language

JavaScript is a scripting language that implements programming in the form of a small program segment. Like other scripting languages, Jav

Ascript is also an explanatory language that provides an easy development process.

Its basic structure form and C, C + +, VB very similar. But unlike these languages, it needs to be compiled first, but in

The program is interpreted on a row-by-line basis during operation. It is combined with the HTML identity to facilitate the user's use of the operation.

2. Object-based language.

JavaScript is an object-based language that can be viewed as an object-oriented one. This means that it can use

Objects that you have already created. As a result, many functions can be derived from the interaction of the object's methods and scripts in the scripting environment

Use.

3. Simplicity

The simplicity of JavaScript is mainly reflected in the following: First, it is a simple and

Compact design, which is a great transition for learning Java. Second, its variable type is the weak type,

Strict data types are not used.

4. Security

JavaScript is a security language that does not allow access to local hard disks and does not store data on the server

, the network documents are not allowed to be modified and deleted, only through the browser for information browsing or dynamic interaction. thereby having

Prevent data loss in an efficient manner.

5. Dynamic Nature

JavaScript is dynamic, and it can respond directly to user or customer input without having to go through a Web service program. It

The response to the user is done in an event-driven manner. The so-called event-driven, refers to the home page (home Pa

In GE), the action generated by an operation is called an event. such as pressing the mouse, moving the window

, select menus, and so on can be considered events. When an event occurs, a corresponding event response may be caused.

6. Development tools

(1), database

In the main application, the database related link application is many, therefore must have the understanding to the database. Cannot simply

Only one database is known, because many database solutions are presented in many real-world developments, so only in understanding

A comparison scenario can be achieved with multiple databases.

The database should be aware of his performance and some basic operational knowledge, as well as the characteristics of the database. And for the JA

The database development of the VA language Web project is mainly for JDBC application, as well as the database transaction processing and connection pool and other advanced

The application of the concept.

(2), Web server

As with databases, you should understand the performance, features, and common sense of the server.

On the application side, the Web server is primarily for configuration and deployment, for directory configuration, for debugging, for configuration file properties

, control of access rights and concurrency, deployment of Java classes, and so on.

(3), Integrated development Environment (IDE):

"Public desire good things, its prerequisite." For Web application developers, a good integrated development environment (IDE:I

ntegrated development enviroment) is very important. A set of current dominant positions in the market

development tool is eclipse.

What technical requirements are required for Java Web Development (simple Web Interface Management system)