iluwatar#1627 fixing sonar issues

fanout-fanin/src/main/java/com/iluwatar/fanout/fanin/App.java

@@ -63,7 +63,7 @@ public static void main(String[] args) {
     final List<SquareNumberRequest> requests =
         numbers.stream().map(SquareNumberRequest::new).collect(Collectors.toList());
 
-    final Consumer consumer = new Consumer(0L);
+    var consumer = new Consumer(0L);
 
     // Pass the request and the consumer to fanOutFanIn or sometimes referred as Orchestrator
     // function

fanout-fanin/src/main/java/com/iluwatar/fanout/fanin/SquareNumberRequest.java

@@ -23,6 +23,8 @@
 
 package com.iluwatar.fanout.fanin;
 
+import java.security.SecureRandom;
+
 import lombok.AllArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
@@ -42,12 +44,15 @@ public class SquareNumberRequest {
    * @param consumer callback class that takes the result after the delay.
    * */
   public void delayedSquaring(final Consumer consumer) {
-    long maxTimeOut = 7000L;
-    long minTimeOut = 5000L;
+
+    var minTimeOut = 5000L;
+
+    SecureRandom secureRandom = new SecureRandom();
+    var randomTimeOut = secureRandom.nextInt(2000);
 
     try {
       // this will make the thread sleep from 5-7s.
-      Thread.sleep((long) (Math.random() * (maxTimeOut - minTimeOut) + minTimeOut));
+      Thread.sleep( minTimeOut + randomTimeOut);
     } catch (InterruptedException e) {
       LOGGER.error("Exception while sleep ", e);
       Thread.currentThread().interrupt();

fanout-fanin/src/test/java/com/iluwatar/fanout/fanin/FanOutFanInTest.java

@@ -29,10 +29,10 @@
 import java.util.List;
 import java.util.stream.Collectors;
 
-public class FanOutFanInTest {
+class FanOutFanInTest {
 
   @Test
-  public void fanOutFanInTest() {
+  void fanOutFanInTest() {
     final List<Long> numbers = Arrays.asList(1L, 3L, 4L, 7L, 8L);
 
     final List<SquareNumberRequest> requests =

fanout-fanin/src/test/java/com/iluwatar/fanout/fanin/SquareNumberRequestTest.java

@@ -26,10 +26,10 @@
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
-public class SquareNumberRequestTest {
+class SquareNumberRequestTest {
 
   @Test
-  public void delayedSquaringTest() {
+  void delayedSquaringTest() {
     Consumer consumer = new Consumer(10L);
 
     SquareNumberRequest squareNumberRequest = new SquareNumberRequest(5L);