Shulou(Shulou.com)06/03 Report--

Editor to share with you what are the differences between java and js, I believe that most people still do not understand, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

Although JavaScript has a close relationship with Java, it is two different products developed by two companies.

Java is a new generation of object-oriented programming language developed by SUN, which is especially suitable for Internet application development, while JavaScript is a product of Netscape, whose purpose is to develop an object-based and event-driven interpretive language that can be embedded in Web pages in order to expand the function of Netscape Navigator. Its predecessor is Live Script; and the predecessor of Java is Oak.

The following is a comparison of the similarities and differences between the two languages:

Object-based and object-oriented

Java is a true object-oriented language, even if you are developing a simple program, you must design objects.

JavaScript is a scripting language that can be used to make complex software that has nothing to do with the network and interacts with users. It is an object based (Object Based) and event driven (Event Driver) programming language. Therefore, it provides a very rich internal objects for designers to use.

Interpretation and compilation

The two languages perform differently in their browsers. The source code of Java must be compiled before it is passed to the client for execution, so the client must have a simulator or interpreter on the corresponding platform, which can realize the bondage of compiling code independent of a particular platform through the compiler or interpreter.

JavaScript is an interpretive programming language, whose source code does not need to be compiled before it is sent to the client for execution, but sends the character code in text format to the client to be interpreted and executed by the browser.

Strong and weak variables

The variables taken by the two languages are different.

Java uses strongly typed variable checking, that is, all variables must be declared before compilation. Such as:

Integer x * * string y * 1234 * 4321

Where Xreply 1234 is an integer and Yreply 4321 is a string.

Variable declaration in JavaScript, with its weak type. That is, variables do not need to be declared before they are used, but the interpreter checks their data types at run time, such as:

X = "4321"

The former shows that x is its numerical variable, while the latter shows that y is a character variable.

The code format is different

Java is an HTML-independent format that must be loaded as external media is referenced in HTML, and its code is stored in a separate document as bytecode.

The JavaScript code is a text character format that can be embedded directly into an HTML document and can be loaded dynamically. Writing an HTML document is as convenient as editing a text file.

Embedding methods are different.

In HTML documents, the identities of the two programming languages are different, and JavaScript uses. To identify, while Java uses... To identify.

Static binding and dynamic binding

Java uses static binding, that is, object references to Java must be done at compile time to enable the compiler to implement strong type checking.

JavaScript uses dynamic binding, that is, object references of JavaScript are checked at run time, and object references cannot be checked without compilation.

The above is all the content of the article "what's the difference between java and js". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.