What are the pitfalls of a Java noob? [closed]

Answer 1

Make sure that you understand OOP instead of making everything static. And find out about stack overflow to ask questions :-).

Answer 2

A small one: searching for a Java class on Google and expecting to find up to date information. Advice: always include the version number i.e search "inputstream 6" not "inputstream". Similarly, beware of tutorials on the net, lot of them are outdated.

Answer 3

what are the things Java does differently than other languages? (on a basic level)

On a basic level it's not different to other OOP language. However, comparing to plain procedural programming it's a whole new world... or a evolved one.

Answer 4

Avoid being more specific than you need to. You might be tempted to think of your storage object as a HashMap:

HashMap myStore = new HashMap();

But I would recommend thinking of it only as a Map (interface):

Map myStore = new Hashtable();

The rest of your code does not need to know how we implemented myStore, it just needs to know that myStore is some kind of Map. This way we can change the implementing type later (HashMap,Hashtable,...), and only one line of code will be affected.

And I chose Hashtable as an example, over HashMap, because Hashtable is thread-safe. In a multi-threaded app, this avoids the problem that two threads reading and changing the same HashMap concurrently can start throwing Exceptions.

Answer 5

There's a collection of semi-official "gotchas", known as the Java Puzzlers, and documented in a book of the same name; you might also find a few screencasts on the web. Periodically, Joshua Bloch and Neal Gafter like to present a bunch of innocuous-looking challenges and proceed to systematically remove any notion you had that you understood even the vaguest basics of the Java language.

On a slightly less cynical note, if you're looking to avoid many of the common design and implementation cock-ups, you might take a look at Effective Java, by the aforementioned Joshua Bloch, which has a wealth of decent advice on how to go about designing several of the important - but frequently badly written - aspects of writing components in Java, including a comprehensive explanation of how to properly implement the contract of equals() and hashCode(), and why you should avoid clone() like the plague.

Oh, and don't compare strings with the == operator.

Answer 6

Obsessing over Design Patterns! I would not worry too much about design patterns to begin with. It is good if you are aware of their existence so that you will know what other members of your team talk about, but what is important right now is just exploring the Core Java APIs. When you feel comfortable with them I'd really put an effort into learning how to write clean and self-documenting code. This will save you a lot of time and effort in the future when you go back and need to remember what you were doing.