used Optional.ofNullable instead of explicitly checking for null

application/src/main/java/org/thingsboard/server/controller/RuleChainController.java

@@ -46,6 +46,7 @@ import org.thingsboard.server.common.data.EventInfo;
 import org.thingsboard.server.common.data.StringUtils;
 import org.thingsboard.server.common.data.edge.Edge;
 import org.thingsboard.server.common.data.exception.ThingsboardException;
+import org.thingsboard.server.common.data.id.AssetProfileId;
 import org.thingsboard.server.common.data.id.EdgeId;
 import org.thingsboard.server.common.data.id.RuleChainId;
 import org.thingsboard.server.common.data.id.RuleNodeId;
@@ -76,6 +77,7 @@ import org.thingsboard.server.service.security.permission.Resource;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.TimeUnit;
@@ -339,8 +341,8 @@ public class RuleChainController extends BaseController {
         RuleNodeId ruleNodeId = new RuleNodeId(toUUID(strRuleNodeId));
         checkRuleNode(ruleNodeId, Operation.READ);
         TenantId tenantId = getCurrentUser().getTenantId();
-        EventInfo eventInfo = eventService.findLatestDebugRuleNodeInEvent(tenantId, ruleNodeId);
-        return eventInfo == null ? null : eventInfo.getBody();
+        return Optional.ofNullable(eventService.findLatestDebugRuleNodeInEvent(tenantId, ruleNodeId))
+                .map(EventInfo::getBody).orElse(null);
     }
 
     @ApiOperation(value = "Is TBEL script executor enabled",