Bugfix: Null handling to not throw exceptions (prebid#3035)

Author: amanpatniajmer

src/main/java/org/prebid/server/auction/gpp/SetuidGppService.java

@@ -1,6 +1,7 @@
 package org.prebid.server.auction.gpp;
 
 import io.vertx.core.Future;
+import org.apache.commons.lang3.StringUtils;
 import org.prebid.server.auction.gpp.model.GppContext;
 import org.prebid.server.auction.gpp.model.GppContextCreator;
 import org.prebid.server.auction.gpp.model.GppContextWrapper;
@@ -44,7 +45,7 @@ private static GppContextWrapper contextFrom(PrivacyContext privacyContext) {
 
     private static Integer toInt(String string) {
         try {
-            return string != null ? Integer.parseInt(string) : null;
+            return StringUtils.isNotBlank(string) ? Integer.parseInt(string) : null;
         } catch (NumberFormatException e) {
             return null;
         }

src/main/java/org/prebid/server/bidder/pubmatic/PubmaticBidder.java

@@ -214,6 +214,9 @@ private BigDecimal resolveBidFloor(String kadfloor, BigDecimal existingFloor) {
     }
 
     private static BigDecimal parseKadFloor(String kadFloorString) {
+        if (StringUtils.isBlank(kadFloorString)) {
+            return null;
+        }
         try {
             return new BigDecimal(StringUtils.trimToEmpty(kadFloorString));
         } catch (NumberFormatException e) {

src/main/java/org/prebid/server/privacy/ccpa/Ccpa.java

@@ -26,6 +26,9 @@ public boolean isNotEmpty() {
     }
 
     public boolean isEnforced() {
+        if (usPrivacy == null) {
+            return false;
+        }
         try {
             validateUsPrivacy(usPrivacy);
         } catch (PreBidException e) {