Move random number generator to HelperFunctions

Signed-off-by: Rahul Rudragoudar <rr83019@gmail.com>

src/main/java/lc/misc/HelperFunctions.java

@@ -1,9 +1,14 @@
 package lc.misc;
 
 import java.awt.*;
+import java.util.Random;
 
 public class HelperFunctions {
 
+  public static int seed;
+
+  private static Random random = new Random(seed);
+
   public static void setRenderingHints(Graphics2D g2d) {
     g2d.setRenderingHint(
         RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
@@ -25,13 +30,18 @@ public class HelperFunctions {
   public static String randomString(final int n, final String characters) {
     final StringBuilder stringBuilder = new StringBuilder();
     for (int i = 0; i < n; i++) {
-      int index = (int) (characters.length() * Math.random());
+      int index = randomNumber(characters.length());
       stringBuilder.append(characters.charAt(index));
     }
     return stringBuilder.toString();
   }
 
-  public static int randomNumber(int min, int max) {
-    return (int) (Math.random() * ((max - min) + 1)) + min;
+  synchronized public static int randomNumber(int min, int max) {
+    return (random.nextInt() * ((max - min) + 1)) + min;
   }
+
+  synchronized public static int randomNumber(int bound) {
+   return random.nextInt(bound);
+  }
+  
 }

src/main/scala/lc/core/config.scala

@@ -6,6 +6,7 @@ import org.json4s.jackson.JsonMethods.{parse, render, pretty}
 import org.json4s.JsonDSL._
 import java.io.{FileNotFoundException, File, PrintWriter}
 import java.{util => ju}
+import lc.misc.HelperFunctions
 
 object Config {
 
@@ -49,12 +50,7 @@ object Config {
   val allowedMedia: Set[String] = captchaConfig.flatMap(_.allowedMedia).toSet
   val allowedInputType: Set[String] = captchaConfig.flatMap(_.allowedInputType).toSet
 
-  private val random = new scala.util.Random(seed)
-
-  def getNextRandomInt(max: Int): Int =
-    random.synchronized {
-      random.nextInt(max)
-    }
+  HelperFunctions.seed = seed
 
   private def getDefaultConfig(): String = {
     val defaultConfigMap =