Is javascript a subset of java?

no. JavaScript and Java are two completely different language architectures. Java is an object-oriented, statically typed, strongly typed language, while JavaScript is an object- and event-driven dynamically typed, weakly typed language; Java's source code must be executed before execution. After compilation, JavaScript code is not required.

The operating environment of this tutorial: windows7 system, javascript version 1.8.5, Dell G3 computer.

Javascript is not a subset of java, they are two completely different things. Although Java and JavaScript are both programming languages, they are two completely different language architectures.

Java is a new generation of object-oriented programming language and a programming language launched by SUN Company, which is particularly suitable for Internet application development. It is an interpreted language with syntax rules similar to C.

JavaScript is a product of Netscape. Its purpose is to extend the functions of Netscape Navigator and develop an object-based and event-driven interpreted language that can be embedded in Web pages; it is a compliance with the ECMA 262 language specification. A realization.

The similarities between javascript and java:

• Their syntax is very similar to the C language;

• They are all object-oriented (although the implementation methods are slightly different);

• JavaScript is designed with reference to Java’s naming rules;

The difference between javascript and java

• ##Java mainly runs on the server; javascript mainly runs on the server In the client browser

  
  

• Java is an object-oriented language, JavaScript is a scripting language, and is an object- and event-driven language.

• Java needs to run on the JVM (Java Virtual Machine) of the JDK or JRE; JavaScript runs on the web browser, so no specific platform is required. Java mainly runs on the server side; JavaScript mainly runs on the client browser.

• Java source code must be compiled before execution, but JavaScript code does not need to be, and can be directly interpreted and executed by the browser.

• The variable types used by JavaScript and Java are different.
  JavaScript is a dynamically typed language; Java is a statically typed language. Java cannot change the length of an array after it is defined, but JavaScript can.

• The variable declaration in JavaScript adopts weak type, that is, the variable does not need to be declared before use, but the interpreter checks its data type at runtime. Java uses strong type variable checking, that is, all variables must be declared before compilation.

• JavaScript is weakly typed, that is, it does not need to be declared before use, but the browser interpreter checks the data type at runtime; Java is strongly typed, that is, all variables are typed before compilation A statement must be made;

• JavaScript’s object-oriented implementation is based on prototype (prototype-based), and Java is based on class (class-based);

• Java’s grammatical rules are much stricter than JavaScript, and its functions are much more powerful.

• Java language code is a language that has nothing to do with HTML; JavaScript language code is a text character format that can be directly embedded in HTML documents and can be loaded dynamically.

• Javascript does not directly operate on text and graphics. It works together with HTML element combinations in Web pages, but it can control the browser and let the browser directly operate on text and graphics. for processing. Java can directly operate on text and graphics.

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