threaded-is-prime

A multi-threaded java application that determines whether a number is prime.

Approach

Given a number n and the number of threads t, the values 2 to sqrt(n) are divided evenly into t parts. These parts are processed by multiple threads to check if the number n is a prime number.

Sample output

How many threads do you wish to create? 4

Created thread #1.
Created thread #2.
Created thread #3.
Created thread #4.

Is 32416190071 a prime number? true
Execution Time: 36 ms

Installation

Please note that this is an eclipse project. To import it on Eclipse:

1. Clone this repository by typing git clone https://github.com/darrensapalo/threaded-is-prime.git on the terminal.
2. Open Eclipse.
3. Go to File > Import > General .. Existing Projects into Workspace > Select root directory .. browse.
4. Select the directory where you cloned the repository. Click finish.
5. Go to the class named PrimeChecker and configure the values as you need them.

Configuration

You can allow the user to either input a number via the system input stream, or you can automatically use a pre-selected prime number. To change this behavior, change this line:

/**
  * Determines whether the user will be asked for an input value.
  */
public static final boolean willGetUserInput = false;
	
/**
  * if <i>willGetUserInput</i> is false, then it will use this value for processing instead.
  */
public static final String defaultValue = Large;

Preselected prime numbers

Conveniently, we provide a small list of prime numbers you can use. To change which default value to use, modify the assignment to the defaultValue static attribute.

public static final String Small   = "472882049";
public static final String Medium  = "27704267971";
public static final String Large   = "32416190071";
public static final String XLarge  = "48112959837082048697";
public static final String XXLarge = "2074722246773485207821695222107608587480996474721117292752992589912196684750549658310084416732550077";