The Difference between Java and JavaScript

The Difference between Java and JavaScript

People often assume that since JavaScript has Java in its name, they are related to each other. While other programmers groan at this coupling, many even feel that the name muddling is part of a marketing ploy. The history of the two programming languages did intersect for a brief moment in time during the early days of Netscape. The evolution of the two languages took such wildly different paths that the common joke is that Java is to JavaScript as ham is to hamburger. But if you are reading this, you probably are interested in a more useful explanation. So, let’s compare the two:

A few years ago, this would have been a simple comparison- Java being defined as a general purpose programming language, and JavaScript being used to make animated and interactive websites. But now that the JavaScript has grown up, the comparison has complicated.

Let’s take a look at some of their similarities and differences from a web development perspective:

1. Both Can Run on Servers

Java has long been a major workhouse of the web, with the application servers running a large share of the web applications seen by the users, both on the public websites and behind the corporate firewalls. While JavaScript has experimented in the server-side realm for a while now, the popularity of Node.js is triggering more JavaScript application servers to occur all over the place.

2. Both Can Run in a Browser

JavaScript runs on most of the modern browsers, and most websites take advantage of this to enhance their user experience. Java can also run in a browser, but have been declining in popularity for various reasons, including security and compatibility. It is reasonable to expect a web visitor to have JavaScript enabled and is common for a website visitor to have Java disabled, especially with the proliferation of mobile browsers.

3. Both Are Influenced by Programming Community

Java uses the Java Community Process to take input on what to embrace in the language in the form of Java Specification Requests. Oracle – the owner of Java- uses these to determine the official implementation of the language. JavaScript, on the flip side, is a derivative of the ECMAScript, which is defined by the European Computer Manufacturers Association (ECMA). Without such open processes, the programming languages have an inclination to become obsolete and more exclusive, thus creating vendor lock-in to a substandard product.

4. Both Have Libraries and Frameworks

Libraries and frameworks help the programmers by providing access to the general and purpose-specific codes that can be reused repeatedly for different products. When used properly, these libraries and frameworks can cut the development time- even by a very noteworthy factor. Both Java and JavaScript are mature enough to have a wide range of libraries and frameworks available to assist developers in a variety of scenarios.

5. Compiled vs. Interpreted

Making changes in the Java application environment can take a number of steps using a specific software to compile and deploy changes, while making changes to JavaScript can sometimes be done with just a simple text editor.

Java code is written in an Integrated Development Environment (IDE) and compiled into bytecodes. These bytecodes are not readable by humans and a Java Virtual Machine (JVM) is required to run it. JavaScript code, on the other hand, is executed by a JavaScript engine in the same syntax in which it is written, while the JavaScript files that are sent over the internet are often compacted to reduce their size.

6. Write-once, Run-anywhere vs. Branching Madness

Java is specially designed to enable developers to write a code once and deploy it to any operating system without making any alterations. Altogether, this does work as designed, although sometimes there are glitches depending on the JVM and the code used. While the JavaScript has a standard through ECMAScript, it is much more vulnerable to the differences in execution environments. While it is really frustrating for the developers to write JavaScript code for different environments, a silver lining that comes here is that the program itself can question the environment to select what branch of code to run in a specific environment.

7. Two-stage vs. Runtime-only Debugging

Java is compiled before being able to run, so if there are any structural problems with the code, they become apparent quickly. Once it starts running, the IDEs often enables the developer to attach to the JVM to debug in real-time. JavaScript is not compiled in the same way, so all the bugs are found in the runtime. Intrinsically, the debugging capabilities of JavaScript are highly reliant on the execution environment, which can vary quite a bit.

If this Java vs. JavaScript Faceoff isn’t enough for you, feel free to dip into the technical, performance-related, or popularity-based assessments. However, the important thing to remember is that they are not the same. So be vigilant while looking for a technical resource and make sure that they have the right experience with the right technology. Got more questions relating to web application development? Leave a comment below and we’d be happy to answer.