Detailed analysis of Java, JavaScript, asp.net, jquery

JAVA and JAVASCRIPT
Java is an object-oriented programming language that can write cross-platform application software. It is a Java programming language and Java platform launched by Sun Microsystems in May 1995 (i.e. JavaSE, JavaEE, JavaME) general name. Java technology has excellent versatility, efficiency, platform portability and security. It is widely used in personal PCs, data centers, game consoles, scientific supercomputers, mobile phones and the Internet. It also has the world's largest professional community of developers. .
The style of Java programming language is very close to C and C++ languages. Java is a pure object-oriented programming language, which inherits the core object-oriented technology of the C++ language. Java abandons the error-prone pointers (replaced by references), operator overloading (operator overloading), multiple inheritance (replaced by interfaces) and other features in the C++ language, and adds a garbage collector function to recycle objects that are no longer referenced. The memory space occupied by the object eliminates the need for programmers to worry about memory management.                                                 The Java platform is a platform based on the Java language. Such platforms are very popular right now. Therefore, Microsoft launched the competing .NET platform and the C# language that imitates Java.


The origin of the name Java: Java is the English name of the Indonesian island of Java, famous for its coffee production. Many library class names in the Java language are mostly related to coffee: such as JavaBeans (coffee beans), NetBeans (network beans), ObjectBeans (object beans), etc. The logos of SUN and JAVA are also a cup of steaming coffee.






JavaScript is a programming language that can make your web pages more lively. It is also the easiest and most convenient language in web design. You can use JavaScript to easily create a friendly welcome message, a beautiful digital clock, a ticker with advertising effects and a simple election, and you can also display the time the browser has stayed. Let these special effects improve the viewability of your web pages.
                                                                                                                                                                                                                                                  JavaScript is a dynamic, weakly typed, prototype-based language that can be executed directly through the browser;     Java is an object-oriented programming language that must be compiled and connected before it can be executed.
　2. JavaScript is written in an HTML file. If you directly view the source code of the web page, you can see the JavaScript program. Therefore, there is no protection. Anyone can copy the program through the HTML file. The program that uses Java on the web page is called Java Applet. (Applet means [small program]), which is separate from HTML files.
　3. The structure of JavaScript is relatively free and loose, while Java, like orthodox programming languages, has a more rigorous structure.
　4. JavaScript does not have functions such as reading and writing files and network control. Java provides these functions. However, JavaScript is more convenient and fast in controlling and interacting with web content.
　5.Javascript mostly runs on the client side, while java mostly runs on the server side.

jquery
jquery is another excellent javascrīpt framework after Prototype. It is a lightweight js library (only 21k after compression). It is compatible with CSS3 and various browsers. jQuery allows users to process HTML documents and events more conveniently, achieve animation effects, and easily provide AJAX interaction for websites. . Another big advantage of jQuery is that its documentation is very complete and its various applications are explained in detail. There are also many mature plug-ins to choose from. jQuery can keep the code and html content of the user's html page separated. In other words, there is no need to insert a bunch of js in the html to call the command. You only need to define the id.
ASP.NETp
ASP is a technology of Microsoft. It is a server -side script technology that enables the script embedded in the webpage to be executed by the Internet server. Refers to Active Server Pages (dynamic server pages), a program running in IIS.
Because ASP.net is a program compiled and run based on a common language, its power and adaptability allow it to run on almost all platforms used by Web application software developers (until now, the author only knows that it can only be used on on Windows 2000/2003 Server/VISTA/7/XP/WIN7). The basic libraries of common languages, message mechanisms, and data interface processing can all be seamlessly integrated into ASP.net Web applications. ASP.net is also language-independent, so you can choose a language that suits you best to write your program, or write your program in many languages. Currently, it supports C# (a combination of C++ and Java), VB, Jscript, C++, F++. In the future, the ability of multiple programming languages ​​to work together will protect your current programs developed based on COM+ and be completely transplanted to ASP.net.
　ASP.NET is generally divided into two development languages, VB.NET and C#. C# is relatively commonly used because it is a unique language of .NET, while VB.NET is designed for previous VB programs and is suitable for previous VB programmers.

AJAX
AJAX stands for "Asynchronous JavaScript and XML" (Asynchronous JavaScript and XML). AJAX is not an abbreviation, but a term created by Jesse James Gaiiett. It refers to a web development technology for creating interactive web applications.
AJAX is not a new programming language, but a technology for creating better, faster, and more interactive web applications.
With AJAX, your JavaScript can communicate directly with the server using JavaScript’s XMLHttpRequest object. This object allows your JavaScript to exchange data with the web server without reloading the page.
　AJAX uses asynchronous data transfer (HTTP requests) between the browser and the web server, which allows the web page to request a small amount of information from the server instead of the entire page.