$ jad demo.MathGame 
  
ClassLoader: 
+-[email protected] 
  +-[email protected] 
  
Location: 
/tmp/arthas-demo.jar 
  
/* 
 * Decompiled with CFR 0_132. 
 */ 
package demo; 
  
import java.io.PrintStream; 
import java.util.ArrayList; 
import java.util.Iterator; 
import java.util.List; 
import java.util.Random; 
import java.util.concurrent.TimeUnit; 
  
public class MathGame { 
    private static Random random = new Random(); 
    private int illegalArgumentCount = 0; 
  
    public static void main(String[] args) throws InterruptedException { 
        MathGame game = new MathGame(); 
        do { 
            game.run(); 
            TimeUnit.SECONDS.sleep(1L); 
        } while (true); 
    } 
  
    public void run() throws InterruptedException { 
        try { 
            int number = random.nextInt(); 
            List<Integer> primeFactors = this.primeFactors(number); 
            MathGame.print(number, primeFactors); 
        } 
        catch (Exception e) { 
            System.out.println(String.format("illegalArgumentCount:%3d, ", this.illegalArgumentCount) + e.getMessage()); 
        } 
    } 
  
    public static void print(int number, List<Integer> primeFactors) { 
        StringBuffer sb = new StringBuffer("" + number + "="); 
        Iterator<Integer> iterator = primeFactors.iterator(); 
        while (iterator.hasNext()) { 
            int factor = iterator.next(); 
            sb.append(factor).append('*'); 
        } 
        if (sb.charAt(sb.length() - 1) == '*') { 
            sb.deleteCharAt(sb.length() - 1); 
        } 
        System.out.println(sb); 
    } 
  
    public List<Integer> primeFactors(int number) { 
        if (number < 2) { 
            ++this.illegalArgumentCount; 
            throw new IllegalArgumentException("number is: " + number + ", need >= 2"); 
        } 
        ArrayList<Integer> result = new ArrayList<Integer>(); 
        int i = 2; 
        while (i <= number) { 
            if (number % i == 0) { 
                result.add(i); 
                number /= i; 
                i = 2; 
                continue; 
            } 
            ++i; 
        } 
        return result; 
    } 
} 
  
Affect(row-cnt:1) cost in 970 ms.