The main skills any web developer needs are the following techniques.
The technology for developing Web applications has become more mature and complex. Now, building a web application requires more than simple HTML techniques. Database access, scripting languages, and management are all skills a Web programmer needs to have. Let’s take a look at what skills are required to become a popular web developer in the market.
Since CERN (European Institute for Particle Physics), a high-energy physics research center near Geneva, launched the Web in 1991, Web technology has evolved from static content and the Common Gateway Interface (CGI) to servlet technology and JavaServer Pages. However, in this more competitive society, a web programmer needs more knowledge. For example, if in the interview you mention that you are familiar with XML and have some experience with JNDI (two technologies that at first glance may not seem closely related to Web programming), then you will leave a deeper impression on your future boss. impression. Assuming that you already know about the Java programming language and object-oriented programming, here are two sets of technologies that a web developer needs in his daily work. The first group includes techniques that every web programmer must possess. The second group contains the techniques you should master to become an advanced programmer.
Basic Skills If you want to call yourself a web developer, here are the skills you must have.
HTML (HyperText Markup Language)
HTML is the language for almost everything displayed on your browser. No wonder HTML is like a web programmer's survival instinct. If you still need to find <tr> or <b> in your HTML, then you really need to improve your HTML skills. The current version of HTML is 4.01, you can learn more about it from http://www.w3.org/TR/1999/REC-html401-19991224/ .
Servlets and JSPs
Java servlet technology is the main technology for developing Java Web applications. It was developed by Sun Microsystems in 1996 and the current version is 2.3, but people are preparing for version 2.4.
JSP is an extension of servlet technology, and the current version is 1.2 (version 2.0 will be finalized soon). Some people think that JSP is a replacement for servlets, but this is not the case. Servlets and JSP are used together for complex web applications.
A good start for Web programming in Java is to learn servlet technology. Even if you plan to use only JSP pages in your Web application, you still need to learn servlet technology. In more complex Web applications, JSP pages are used only for display, while JavaBeans and custom tag libraries are used to embed business logic. That is: you must also be proficient in JavaBeans and custom tag libraries.
JavaScript
JavaScript is a scripting language that runs in all major browsers. You use JavaScript for client-side programming. The most important task in client-side programming is validating user input. The benefit of using client-side input validation is to reduce server workload and improve response time. Additionally, JavaScript can be used for redirections, cookie handling, controlling applets, creating navigation trees, opening a new instance of a browser, and more.
SQL (Structured Query Language) and JDBC (Java Database Connectivity)
Today, most web applications include accessing data in relational databases. As a web programmer, you need to know how to store, retrieve, and manipulate data in a database. Sometimes, you also need to design the database and build tables and other structures in the database. SQL is the language used to manipulate data in the database. You typically need to write SQL statements (often dynamically), pass them to the database server, and get the data back (if any).
Using the Java language, you need to use JDBC to help the web application communicate with the database server. JDBC has two parts: JDBC Core API (Application Programming Interface) and JDBC Optional Package API. The first group is used to perform basic data operations, such as creating a connection or reading, updating, and deleting records in a table. The second group provides more advanced database connection features such as connection pooling, transactions, and RowSet. The current version of JDBC is 3.0, and the API is included in J2SE v. 1.4.
Web Container Management and Application Deployment Your servlets and JSP pages run in an engine called a servlet/JSP container or Web container. You need to at least know how to deploy your web resources for testing as well as production runs. For example, if you use Tomcat, one thing you need to know is how to map the application in the configuration file (server.xml) so that Tomcat knows how to call your JSP page. Additionally, you need to know where to save your libraries and how to create application deployment descriptors.
XML (eXtensible Markup Language)
XML is a successful rising star in the computer field. Developed by the World Wide Web Consortium in 1996, XML is now a widely recognized standard for data exchange and extensible data structures. XML plays an important role in Java Web development. For example, each application's deployment descriptor is in XML format. Moreover, if you are developing Web services, you will use SOAP (Simple Object Access Protocol), which is mainly based on HTTP and XML.
In addition, in Web applications, XML may also be used to store hierarchical data.
Model 2 architecture is the most advanced technology in its category. This structure is recommended for building fairly complex Java web applications. The Model 2 structure is based on the Model-View-Controller design paradigm.
Advanced Techniques The following techniques will separate you from the beginners.
JSTL (JSP Standard Tag Libraries), Jakarta Taglibs project, and other libraries To speed up application development, you should often reuse code. Simply put, code reuse means that if someone has already written code to perform certain functions, you are better off using that code rather than writing it yourself. Therefore, JSP allows you to use custom tags. There are several libraries you can use, the most popular being those from Apache's Jakarta Taglibs project. This package can be downloaded from http://jakarta.apache.org/taglibs/index.html , and you can use anything you find ready-made in this package before starting to create new classes.
JSTL has recently become a standard. Other tag libraries are available free or commercially.
Apache Struts project
Struts is an Apache-sponsored public resource project that provides a framework for building Model 2 Java Web applications. Struts provides its own Controller component for the MVC structure, uses EJB, JDBC and JNDI for Model, and uses JSP and other technologies for View. You can find more detailed information about this project from its website: http://jakarta.apache.org/struts/index.html .
XHTML (Extensible HyperText Markup Language)
XHTML is a technology that strives to combine HTML and XML. You can think of XHTML as the next generation of HTML. Its current version is 1.0 (the second version was released on August 1, 2002). XHTML is not as popular as HTML, but it will play a more important role in the future. According to Web design expert Molly Holzschlag, the main reason driving companies to switch to XHTML is U.S. laws on public access (accessibility). For more information on XHTML, see Holzschlag's interview.
DHTML (Dynamic HTML)
DHTML allows people to interact more on your website. For example, using DHTML, you can easily create and display a submenu when the user moves the mouse over a link. The biggest challenge with using DHTML is creating cross-browser pages. Indeed, in theory, page design should be handled by artists, where dynamic HTML is generated by using a tool. However, a web programmer is usually responsible for integrating all the pieces, and if the code generated in the page is broken, you will need to understand DHTML to fix it.
Applet Programming
Applets used to be important in providing interactivity, especially before the advent of DHTML. Now, the role of applets has been reduced, and more programmers no longer use applets. Microsoft's decision not to provide default support for applets in its new browser significantly reduces the role of applets in Web applications. However, applets are not dead. For certain tasks, such as displaying news headlines, applets are still irreplaceable, and applets don't create the headache of cross-browser compatibility.
HTTP protocol
Java Web programmers often use higher protocols than HTTP, such as using servlets and JSP APIs. These APIs hide the complexity of the HTTP protocol. Therefore, you can still build important applications without knowing much about the HTTP protocol. Only if you need to deal with raw data, such as uploading or transmitting files as attachments, do you need more knowledge about the protocol.
EJB (Enterprise JavaBeans)
EJB is a part of J2EE and is important when scalability and power are the main requirements of your web application. There are three types of EJBs in the current specification (EJB 2.0): session EJBs, entity EJBs, and message driven EJBs. A new specification, version 2.1, is under design.
JNDI (Java Naming and Directory Interface)
JNDI is important when you are developing enterprise beans because access to an EJB is done through the JNDI naming service. Use a naming service to find an object associated with a specific name. In an EJB context, a naming service finds an enterprise bean, given the bean's name. Therefore, understanding JNDI is crucial in developing an EJB application. In addition, JDBC can use JNDI to access a relational database.
Other Tools Knowing where to find specific support tools can often help your career grow. For example, if you happen to be assigned to do a task on benchmarking, you'll be happy to know that you can download Jmeter from Apache's Jakarta Project. In addition, if you need to send the output results in PDF format, it is recommended that you use the Java-PDF library, which can be downloaded for free from http://www.lowagie.com/iText/ . Internet technology is broad and developing rapidly. This means that as a Web programmer, you should always pay attention to what new technologies are emerging in the industry and what major events are happening. There is no greater resource in this regard than the Internet itself.
About the author:
Java for the Web
with Servlet, JSP, and EJB
Budi Kurniawan is an IT consultant who specializes in Internet and object-oriented programming and teaches Java and Microsoft technologies. He is the author of the best-selling Java for the Web with Servlets, JSP, and EJB: a Developer's Guide to Scalable Solutions (New Riders), and developed the most popular Java Upload Bean, which you can download from BrainySoftware. com got it, and many important companies licensed it and used it in their projects. Budi can be contacted at [email protected] .