Which is the best way to implement prime number finding algorithms in Java? How do we make library classes and use then in Java?

Question

I want to make library classes in Java and use them in my future programs. I want these library classes to find prime numbers upto a certain number or even the next prime number or you can say solve most of the basic things related to prime numbers.

1. I have never made a Java Library Class. I aim to learn that doing this. Please help me without that by pointing out a tutorial or something. I am familiar with netbeans IDE.
2. I found out a few algorithms like Sieve of Eratosthenes and Sieve of Atkin. It would be great if you can point out a few more such efficient algorithms. I don't want them to be the best but at least good enough. My aim is to learn few things by implementing them. Because I have little practical coding experience I want to do it to improve my skills.
3. My friend suggested me to use Stream Classes and he was talking something about implementing it by giving the output of one file as an input to another to make my code clean. I didn't understand him very well. Please pardon me if i said anything wrong. What I want to ask in this point is, is that an efficient and OO way of doing what i want to do. If yes please tell me how to do that and if not please point out some other way to do it.

I have basic knowledge of the Java language. What I want to accomplish through this venture is gain coding experience because that is what everyone out here suggested, "to take up small things like these and learn on my own"

thanks to all of you in advance

regards

shahensha

EDIT: In the Sieve of Eratosthenes and others we are required to store the numbers from 2 to n in a data structure. Where should I store it? I know I can use a dynamic Collection, but just a small question...If i want to find primes in the order of billions or even more (I will use Big Integer no doubt), but all this will get stored in the heap right? Is there a fear of overflow? Even if it doesn't will it be a good practice? Or would it be better to store the numbers or the list (on which we will perform actions depending on the algorithm we use) in a file and access it there? Sorry if my question was too noobish...

Answer 1

"Sieve of Eratosthenes" is good algorithm to find the prime numbers. If you will use google you can find ready implementation in java.