Resolve "Fixing Problem with duplicate Entry in Statistics"

Related to #540

src/main/java/at/ac/uibk/gitsearch/service/StatisticsService.java

@@ -24,6 +24,7 @@ import org.springframework.stereotype.Service;
  * {@link at.ac.uibk.gitsearch.domain.Statistics}.
  */
 @Service
+@SuppressWarnings("PMD.TooManyMethods")
 public class StatisticsService {
 
   private final Logger log = LoggerFactory.getLogger(StatisticsService.class);
@@ -85,7 +86,7 @@ public class StatisticsService {
   public Optional<StatisticsDTO> findOneByExerciseID(String id) {
     log.debug("Request to get Statistics : {}", id);
     final List<Statistics> hits = statisticsRepository.findByExerciseID(id);
-    if (hits.size() == 0) {
+    if (hits.isEmpty()) {
       return Optional.empty();
     } else if (hits.size() > 1) {
       log.error(
@@ -118,7 +119,7 @@ public class StatisticsService {
 
   @Transactional
   public Stream<Statistics> findStatisticsOrphans() {
-    final Stream<Statistics> streamStatisticsOrphans = statisticsRepository
+    return statisticsRepository
       .streamAll()
       .filter(stats -> {
         try {
@@ -133,7 +134,6 @@ public class StatisticsService {
         }
         return false;
       });
-    return streamStatisticsOrphans;
   }
 
   public void cleanUpDuplicates() {
@@ -177,16 +177,14 @@ public class StatisticsService {
 
   public Optional<Statistics> getStatistics(String exerciseID) {
     List<Statistics> statistics = statisticsRepository.findByExerciseID(exerciseID);
-    if (statistics.size() == 0) {
+    if (statistics.isEmpty()) {
       return Optional.empty();
     }
-    if (statistics.size() > 0) {
-      if (statistics.size() > 1) {
-        log.error(
-          "There are duplicate statistic entries {}!",
-          statistics.stream().map(e -> "id " + e.getId() + "/" + e.getExerciseID()).collect(Collectors.joining(", "))
-        );
-      }
+    if (statistics.size() > 1) {
+      log.error(
+        "There are duplicate statistic entries {}!",
+        statistics.stream().map(e -> "id " + e.getId() + "/" + e.getExerciseID()).collect(Collectors.joining(", "))
+      );
     }
     return Optional.of(statistics.get(statistics.size() - 1)); // return last
   }
@@ -210,8 +208,8 @@ public class StatisticsService {
 
   private void updateStatisticsForExercise(String exerciseID, StatisticsUpdater updater) {
     List<Statistics> statistics = statisticsRepository.findByExerciseID(exerciseID);
-    Statistics entry = null;
-    if (statistics.size() == 0) {
+    Statistics entry;
+    if (statistics.isEmpty()) {
       entry = new Statistics();
       entry.setExerciseID(exerciseID);
       entry.setViews(0);