Thinking in Code: JavaScript and Java

JavaScript is not Java.

Let me repeat that again: JavaScript is to Java what Hamster is to Ham.

There is no direct correlation, other than the fact that they both are a form of programming language, and a way to instruct a computing environment to perform specific tasks. Their paradigms are completely different, and they are not formed of the same types of features. Let me highlight some of the key features of each language:

JavaScript is...

• a functional language with basic facilities for forcing object oriented notation, despite not being object oriented at all.
• a dynamic, loosely typed language that is event driven
• typically used in the web browser, though there are server side implementations that are catching on.

Java is...

• a mostly object oriented language
• a static, strongly typed language
• typically used for implementing very powerful server based processes which are cross platform compatible

Every language has it's own strengths and weaknesses, and it's own way to code appropriately in. This has given birth to many books such as "Effective Java," "Thinking in Java," "The Well Grounded Rubyist" and "Javascript, the Good Parts." Each of these books focuses on where each language excels. The reason that there are so many is because each language has it's own way of thinking. If they didn't, there wouldn't be any reason to have so many books.

Why Does it Matter?

I have run across an awful lot of JavaScript code that was clearly written by a Java developer. Over architected and excessively complex code which takes hundreds of times the CPU cycles than ten lines of well written, clear, easy to use, self documenting code. This highlights the differences between the two languages, and the two different thought processes between the two. The correct way to implement a particular feature in one programming language may not only be wrong in another language, but may go against the very intention and fabric of the language. This is why companies hire programmers to participate in the development of a particular application based on language, rather than just hiring the best generalist that they can find. Not that generalists don't have their place, by all means they do. But in order to be well grounded in many languages, it not only takes passion for coding, but motivation and drive. Despite what you may believe, you're probably not one. They are few and far between, and when found, they are worth their weight in gold.