Evaluation of three mainstream Web development technologies: JSP

Why does JSP appear? Java has encountered many difficulties when pushing it to developers. first, Java lacks extensive support from mainstream systems, and there is a lack of application methods that can be directly referenced on all platforms and technologies. At this time, java is moving towards positive progress at each application layer, and it has taken a firm step in both the fields that you are good at and those that are not good. What makes Web technology JSP the most possible cause? Java/> Java has encountered many difficulties when pushing it to developers. first, java/> Java lacks extensive support from mainstream systems, however, there is a lack of application methods that can be directly referenced in all platforms and technologies. At this time, java is moving towards positive progress at each application layer, and it has taken a firm step in both the fields that you are good at and those that are not good. Among them, the most exciting thing for Web technicians is the emergence of Java Servlet and the gradual maturity of JSP. this step makes Java formally go to the stage of Web development technology. Java uses its cross-platform technology to quickly deploy java applications on various platforms, and can be written and run anywhere. It uses this advantage to skillfully combine java versatility, jsp usability, and servlet speed, the skills on platform deployment effectively shield java speed issues, so Java can be quickly popularized among members of Web developers. With powerful background such as Java Bean, EJB, Java Application Server, and Java Transaction Server, we have developed mature applications.

What kind of language is Jsp? In fact, JSP is Java, but it is a special Java language. It adds a special engine that automatically initializes some objects in the HTTPServlet class for users to use, the user does not have to worry about the previous work. At the same time, this engine introduces Java Servlet Code (. java file)-> Java Runtime Bin Code (. class file). This is why the CPU runs very high when we run JSP for the first time. it actually calls the jsp engine to generate a java file, you can use javac to compile it to the class file to execute it. At the same time, it also explains why the speed is faster after the first running, as long as the jsp file does not change, this operation will no longer be performed (unless you delete the class file ). So, what kind of jsp does java have? like asp, the real strength of jsp is something we will never see!

Strong:

1. one write task runs everywhere. This is a programmer's dream and also the nightmare of the former programmer. to run on different platforms, many programmers can rewrite code line by line. At this point, java has given me the perfect answer. it is better than php. in addition to the system, you do not need to make any changes to your code.

2. the system supports multiple platforms. I have seen consistent java servlet/jsp Web Server/Application Server on almost all platforms ...... It allows you to develop in any environment, deploy the system in any environment, and expand in any environment. Compared with asp/php, the limitations are obvious.

3. powerful scalability. From only one small jar file, you can run servlet/jsp, cluster and load on multiple servers are horizontal, and transaction and message processing on multiple applications ...... one server to countless server, Java shows the vitality of a giant.

4. diversified and powerful development tool support. This is similar to asp. java already has many excellent development tools and many of them can be obtained for free, and many of them can run smoothly on multiple platforms. If you use them carefully, you will find that they are much more powerful than when you first see them.

Weak:

1. just like ASP, some advantages of Java are just a fatal issue. It is precisely for the purpose of cross-platform functionality and extreme scaling capabilities that greatly increase the complexity of the product. In this case, the number of segments it needs to be divided into during expansion and the number of products in the java system. So you need to see jre, jdk, jsdk, jswdk ......, In fact, as long as they are effectively matched together, they can produce powerful performance, which is inseparable, but for a beginner: "Are there any mistakes! Is it necessary for me to run a jsp with so many messy things !"

2. from the first day of appearance, I was scolded by my opponent as "slow as an old ox ". Really, when I ran my jsp for the first time, I thought my machine crashed and killed the process! It was a nightmare for users to compile and run for the first time. during development, I often dream of waiting for the job manager to drop down at night when the CPU of WinNT is fully green.

3. skills or skills. The cost must be paid for a short point. Java runs at a speed that uses the class resident memory. Therefore, in some cases, the memory used by Java is actually the "lowest performance/price ratio" compared to the number of users. On the other hand, it also requires hard disk space to store a series of. java files,. class files, and corresponding version files.

4. lack of systematic information. This may not be said, but sun is doing very poorly in China, and there are very few java resources in China. so far I have not seen a jsp book in the bookstore, the number of java-related books (Chinese version) is less and less. Let's take a look at a lot of things, but we are still talking about the old products such as Visual J ++ or Java 1.1.

Summary:

Applicable to: developers with strong learning ability and patience. Applications with low investment but high scalability.

Applicable platform :...... (Too many applications, but not one by one) applicable applications: applications with high reliability on the Internet/Intranet, and application systems with the combination of Internet/Intranet and Client/Server

Learning method: Java Doc and a series of Internet source code resources in the java site (sorry, I really cannot provide better suggestions, and some of them are the capabilities and luck of everyone, and help from netizens on Inetnet)

Recommended development tools: JBuilder/Visual Age for java (I have never used this, but it is strongly recommended)/Sun Forte for JavaKAWA

Recommended development environment: Windows NT/Windows 2000 development system JBuilder 3.5 (which can be a Web Server or even no longer require other tools) Tomcat 3.1JDK 1.3 (which can be left uninstalled) access 2000/p ii 266/128 m ram/9G HD

Recommended application environment (minimum): RedHat Linux 6.2/MySQL 3.22/Apache 1.3.12/Tomcat 3.1/JDK 1.3 Beta/PIII 500/512 m ram/9G HD

Recommended application environment (best): Solaris 8/Sybase 11/iPlanet Enterprise Web Server 4.1/JDK 1.3 Beta/Sun Netra T1/1g ram/18G HD