You can also assign different data types to the same variable along the way and JS will not complain about it - this is why it is known as dynamically typed, because the type of each variable can change as the program runs. Consider the following example:. In strongly-typed programming languages such as Java, type conversions must generally be handled explicitly by the developer.
Consider this example:. If we try to pass in val1 along with the val2 to the getSum function, and try to compile, we would get an error:. Unresolved compilation problem: The method getSum int, int in the type MyClass is not applicable for the arguments String, int. In order to get the sum, first you would convert the string value of "1" to an integer by typecasting, then the add variable values to get 3.
However, this is not the case with weakly typed languages such as JavaScript. Weak typing allows you to use different types of values without using explicit typecasting.
Instead, an implicit conversion is performed at the runtime. For example, you could add a string and an integer value to get an implicitly casted string value. Note that in this example JS will use the datatype of the first variable in the expression to decide how to do the implicit conversion. In this case, since the "1" is a string, JS will convert the 2 integer value to a string and then concatenate the values to get a string result of "12". Java is a class-based programming language while JavaScript is a prototype-based programming language.
In Java, all properties, methods, and fields are defined by a class. In fact, they must exist within a class or the program will fail to compile. Classes are the blueprint for the objects and they are abstract.
When you instantiate a class create an object from it , you get an instance of that class. Instances have the exact same properties and methods as their parent classes.
Here, we created an Employee class with a constructor that takes name and id as parameters. We can instantiate this class and access all of its properties via the instantiated object:. Note that once an object is created instantiated you can not add extra properties to that particular object. In Java, you can only use and modify what already has been defined by the class itself.
JavaScript, however, does not enforce this restriction. Every object in JavaScript uses the prototypical Object as a template to define its initial set of properties. Unlike Java, objects in JavaScript can be assigned additional properties even after creation. These new properties remain specific to the particular object and do not affect others that use the same prototype. It means that the variables declared inside the block, can only be used in the block scope, not outside of that particular block.
Above, we added 2 more functions to the object even after the creation. If you go ahead and run the functions, you would get the results as expected:. Java is a multi-threaded programming language. Multi-threading refers to the parts of your application that can run concurrently to handle different tasks. Using multi-threading can greatly increase the performance of your program depending on your methods and tasks, but can be harder and more expensive to maintain from a development perspective.
JavaScript is a single-threaded programming language. However, JavaScript can also call functions asynchronously. Meaning that concurrency is possible with the JS too. I know that sounds weird but it is possible. JavaScript is a single-thread that runs on the event loop, which means it has only one call stack. A call stack is a computing structure where JavaScript code instructions get pushed into, get executed, and pop out a result once execution is done.
The call stack is a generic term that is used for other programming languages too. One of the main purposes of the stacks is to keep track of all the instructions that are running in a program or a subroutine to be precise. The call stack is not to be confused with a callback function.
A callback function is a function passed as an argument into another function. For instance, if you have a sayName function and you want to execute it only after waiting a certain interval of time, then you could pass that function into the setTimeout function as a parameter.
You can change it after it runs to time and time again. Once Java is compiled, you cannot change it. You can still change the original text and then compile it again. Which is the better language for better web applications? One of the biggest strengths that JavaScript has going for it is that it can be understood by humans.
This makes coding on JavaScript much easier and makes the language more robust too. It also gives a huge benefit over Java in terms of speed. You can create web page events and elements faster using JavaScript than with Java. These commands are directly embedded into existing HTML commands.
Apart from the ease of use, JavaScript is also slightly more forgiving to the programmer than Java. It gives the programmer more freedom in terms of creating objects with a prototype basis. Meanwhile, Java is more rigid and requires all the classes and instances to be defined and denoted. JavaScript also enables you to call on items that are already existing, like the browser itself or the status bar, and lets you play with only that part.
Java, not so much. It is more geared towards where it is needed almost all the time, while JavaScript is geared towards web pages where it is only part of the page being displayed. However, both can really make good web page events, and both Java and JavaScript can offer a higher level of interaction between website and user than would be possible with HTML alone.
Nevertheless, they are not equal in most ways. So, now that you know the few similarities difference between Java vs JavaScript, the final question is: which one should you opt for? The answer to this is: whichever language better fits your needs. Neither language is superior to the other. JavaScript and the applets are most often offered as fully functional items on the internet. This means that you can simply get them from the internet and use them on your own page, so long as you have the required permission.
There are, in fact, several websites that specialize in providing applets and JavaScript. They do nothing else. For applets, Gamelan. If you want to learn how to implement the items on your web page, you can find lots of great tutorials and resources online. However, keep in mind that they do not teach you how to write the languages; they merely show you how to place them on your website.
Java is a multi-platform, object-oriented, and network-centric, programming language. It is among the most used programming language. It also used as a computing platform, and it was first released by Sun Microsystem in It was later acquired by Oracle Corporation.
JavaScript is a scripting language that helps you create interactive web pages. Nowadays JavaScript also using technologies like Node js. Here are the important features of Java. Improve Article. Like Article. It can insert dynamic text into HTML. JavaScript JS is not similar or related to Java. Both the languages have a C like a syntax and are widely used in client-side and server-side Web applications, but there are few similarities only.
Java : Java is an object-oriented programming language and have virtual machine platform that allows you to create compiled programs that run on nearly every platform.
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