Navigating through Javadocs

I am new to Java and as a first I read through a couple of books that deal with the Java language.

I had a couple of questions about the java docs. How does one 'navigate' them? Is it possible to learn new concepts using solely Javadocs?

Here's an example - I want to use nio to build an 'event' based lock-free chat server. For that I started looking through the J2SE 6 Java API docs: http://download.oracle.com/javase/6/docs/api/

I saw there were several packages that deal with nio - java.nio, java.nio.channels, java.nio.channels.spi, java.nio.charset, java.nio.charset.spi

I looked over the c开发者_如何学编程lasses, interfaces etc. But I didn't actually know how to start using the 'nio' concepts. What documentation does one use to learn such concepts effectively?

Apologies if my question is a bit long winded or too conceptual. I am trying to figure out my way around the Java eco-system to find the best way to self-learn concepts effectively.

Thanks!

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An API documentation is for lookup of classes and methods. It's rarely useful for learning concepts. Use tutorials (or books) for that, e.g. the one from Oracle.

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This might get you started,

https://www.ibm.com/developerworks/java/tutorials/j-nio/

It's a kick start for NIO and has links to resources such as example applications

Happy Coding!

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Javadocs basically are used/written to explain the API one has written. I will not suggest them if you want to learn java. But if you want to learn someone's API, then that is the thing. Javadovs also help to understand the class hierarchies and dependancies.