Question

2.) Analyze the modified Java code PrimeFinderInterupt

1. Make this program to RUN and provide a screenshot of the output
2. Describe the additional functionality of the PrimeFinderInterrupt
3. 1. NOTE IF your original PrimeFinder ran faster than 7 seconds, change the code line: "if (++index > 7 )" to have a number less than the time to run your original code.

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Below is the "PrimeFinderInterupt" java code:

package com.java24hours;

public class PrimeFinderInterrupt implements Runnable {
Thread go;
StringBuffer primes = new StringBuffer();
int time = 0;
int index = 1;

public PrimeFinderInterrupt() {
start();
while (primes != null) {
System.out.println(time);
if (++index > 3 )
{
System.out.println("cancel thread after 3 seconds... too long");
stop();
}
try {
Thread.sleep(1000);
} catch (InterruptedException exc) {
// do nothing
}
time++;
}
}

public void start() {
if (go == null) {
go = new Thread(this);
go.start();
}
}
  
public void stop()
{
go.interrupt();
}

public void run() {
int quantity = 1_000_000;
int numPrimes = 0;
// candidate: the number that might be prime
int candidate = 2;
primes.append("\nFirst ").append(quantity).append(" primes:\n\n");
  
while (numPrimes < quantity) {
if (isPrime(candidate)) {
primes.append(candidate).append(" ");
numPrimes++;
}
candidate++;

if (Thread.currentThread().isInterrupted())
{
System.out.println("Thread timeout... exiting");
primes = null;
return;
}
}
  
System.out.println(primes);
primes = null;
System.out.println("\nTime elapsed: " + time + " seconds");
}

public static boolean isPrime(int checkNumber) {
double root = Math.sqrt(checkNumber);
for (int i = 2; i <= root; i++) {
if (checkNumber % i == 0) {
return false;
}
}
return true;
}

public static void main(String[] arguments) {
  
long startns = System.nanoTime();
long startms = System.currentTimeMillis();
double a=-12.225, b=4, c=0;
for (int idx = 0; idx < 5000; ++idx)
{
c = a + b;
}
long endns = System.nanoTime();
long endms = System.currentTimeMillis();
long diffns = endns-startns;
long dms = endms - startms;
System.out.println("time of 500 divides in ns and ms =" + diffns + " " + dms);
  
new PrimeFinderInterrupt();
}
}

Answer 1

Addition function of primeInterrupt is a thread validation check that if thread takes more than time assigned time it stop that thread from running forever give control backs to main thread