This week's book giveaways are in the Java EE and JavaScript forums.
We're giving away four copies each of The Java EE 7 Tutorial Volume 1 or Volume 2(winners choice) and jQuery UI in Action and have the authors on-line!
See this thread and this one for details.
The moose likes Beginning Java and the fly likes Arrays Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login

Win a copy of The Java EE 7 Tutorial Volume 1 or Volume 2 this week in the Java EE forum
or jQuery UI in Action in the JavaScript forum!
JavaRanch » Java Forums » Java » Beginning Java
Bookmark "Arrays" Watch "Arrays" New topic


Nickk Singhal

Joined: Dec 09, 2011
Posts: 4
how to generate random number without using random class
Joanne Neal

Joined: Aug 05, 2005
Posts: 3477
You should read NotACodeMill and then update your post.

NB - this was a reply to the original post which was just a question copied from a book/exam paper/whatever and if i remember properly had nothing to do with random numbers.

Jesper de Jong
Java Cowboy
Saloon Keeper

Joined: Aug 16, 2005
Posts: 14114

You could implement your own random number generator. But beware that it is not easy to create "good" random numbers (random numbers which are truly random, or which at least have a statistical distribution that comes close to being really random). Several algorithms have been invented to generate pseudo-random numbers; do some research to learn more about them.

Java Beginners FAQ - JavaRanch SCJP FAQ - The Java Tutorial - Java SE 7 API documentation
Scala Notes - My blog about Scala
Rob Spoor

Joined: Oct 27, 2005
Posts: 19674

Or just use Math.random(). It generates a double value between 0.0 (inclusive) and 1.0 (exclusive), so multiply it by X and cast to int to get an int value between 0 (inclusive) and X (exclusive).

How To Ask Questions How To Answer Questions
Consider Paul's rocket mass heater.
subject: Arrays