title: Handler dispatch failed; nested exception is java.lang.StackOverflowError with root cause
body: <p>Getting this error when jpa tries to fetch the object from database.</p>
  <p>Error : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Handler dispatch failed; nested exception is java.lang.StackOverflowError] with root cause</p>
  <p><strong>UserController</strong>
  In this the getUsers method doesn't work and caused error</p>
  <pre><code>
  @RestController
  @RequestMapping(&quot;user&quot;)
  public class UserController {
  
      private final Logger log = LoggerFactory.getLogger(UserController.class);
  
      @Autowired
      private UserService userService;
  
      @Autowired
      private RoleService roleService;
  
      @PostMapping(&quot;/add&quot;)
      public MessageDto addUser(@RequestBody UserDto userDto)
      {
          log.info(&quot;Post call have been received at user/add with DTO &quot; + userDto);
                                               //Set&lt;UserRoleDomain&gt;
          UserDomain userDomain = userService.mapUserDtoToDomain(userDto);
          return userService.add(userDomain, roleService.add(userDomain));
      }
  
      @GetMapping(&quot;/get/{userName}&quot;)
      public UserDto getUsers(@PathVariable(&quot;userName&quot;) String userName)
      {
          log.info(&quot;Get call have been received at user/get/ &quot;+userName);
          return userService.getById(userName);
      }
  
  }
  </code></pre>
  <p><strong>UserService</strong></p>
  <pre><code>
  @Service
  @Transactional
  public class UserService {
  
      private final Logger log = LoggerFactory.getLogger(UserService.class);
  
      @Autowired
      private ObjectMapper objectMapper;
  
      @Autowired
      private UserRepository userRepository;
  
      @Autowired
      private RoleRepository roleRepository;
  
      @Autowired
      private UserRoleRepository userRoleRepository;
  
      public MessageDto add(UserDomain userDomain , Set&lt;UserRoleDomain&gt; userRoles)
      {
              // UserDomain userDomain = mapUserDtoToDomain(userDto);
              if( userRepository.findByUserName(userDomain.getUserName())!=null) // causing error
              {
                  String responseMessage = &quot;User is already register with name ! &quot;+userDomain.getUserName();
                  MessageDto messageDto = new MessageDto(responseMessage);
                  log.info(responseMessage);
                  return messageDto;
              }
              else {
  
                  for (UserRoleDomain userRoleDomain: userRoles) {
                      System.out.println(&quot;result : &quot;+userRoleDomain.getRoleDomain());
                      roleRepository.save(userRoleDomain.getRoleDomain());
                  }
  
                  userDomain.getUserRoleDomains().addAll(userRoles);
                  userRepository.save(userDomain);
                  String responseMessage = &quot;User has been added with Id &quot; + userDomain.getUserId();
                  MessageDto messageDto = new MessageDto(responseMessage);
                  log.info(responseMessage);
                  return messageDto;
              }
      }
  
      public UserDto getById(String userName)
      {
         UserDomain userDomain =  userRepository.findByUserName(userName);
         return mapUserDomainToDto(userDomain);
      }
  
      public UserDomain mapUserDtoToDomain(UserDto userDto)
      {
          return objectMapper.convertValue(userDto , UserDomain.class);
      }
  
      public UserDto mapUserDomainToDto(UserDomain userDomain)
      {
          return objectMapper.convertValue(userDomain , UserDto.class);
      }
  
  }
  </code></pre>
  <p><strong>This is my terminal</strong></p>
  <pre><code>2021-07-31 13:57:50.549  WARN 13691 --- [nio-8881-exec-1] o.h.e.loading.internal.LoadContexts      : HHH000100: Fail-safe cleanup (collections) : org.hibernate.engine.loading.internal.CollectionLoadContext@17f80723&lt;rs=HikariProxyResultSet@763024380 wrapping Result set representing update count of -1&gt;
  2021-07-31 13:57:50.549  WARN 13691 --- [nio-8881-exec-1] o.h.e.loading.internal.LoadContexts      : HHH000100: Fail-safe cleanup (collections) : org.hibernate.engine.loading.internal.CollectionLoadContext@38b516d2&lt;rs=HikariProxyResultSet@1651373951 wrapping Result set representing update count of -1&gt;
  2021-07-31 13:57:50.558 ERROR 13691 --- [nio-8881-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Handler dispatch failed; nested exception is java.lang.StackOverflowError] with root cause
  
  java.lang.StackOverflowError: null
      at java.base/java.lang.String.indexOf(String.java:1578) ~[na:na]
      at java.base/java.lang.String.indexOf(String.java:1535) ~[na:na]
      at java.base/java.net.URLStreamHandler.parseURL(URLStreamHandler.java:143) ~[na:na]
      at java.base/sun.net.www.protocol.file.Handler.parseURL(Handler.java:67) ~[na:na]
      at java.base/java.net.URL.&lt;init&gt;(URL.java:674) ~[na:na]
      at java.base/java.net.URL.&lt;init&gt;(URL.java:541) ~[na:na]
      at java.base/jdk.internal.loader.URLClassPath$FileLoader.getResource(URLClassPath.java:1221) ~[na:na]
      at java.base/jdk.internal.loader.URLClassPath.getResource(URLClassPath.java:314) ~[na:na]
      at java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(BuiltinClassLoader.java:695) ~[na:na]
      at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:621) ~[na:na]
      at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:579) ~[na:na]
      at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) ~[na:na]
      at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) ~[na:na]
      at com.mysql.cj.jdbc.ClientPreparedStatement.executeQuery(ClientPreparedStatement.java:1020) ~[mysql-connector-java-8.0.25.jar:8.0.25]
      at com.zaxxer.hikari.pool.ProxyPreparedStatement.executeQuery(ProxyPreparedStatement.java:52) ~[HikariCP-4.0.3.jar:na]
      at com.zaxxer.hikari.pool.HikariProxyPreparedStatement.executeQuery(HikariProxyPreparedStatement.java) ~[HikariCP-4.0.3.jar:na]
      at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:57) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.getResultSet(AbstractLoadPlanBasedLoader.java:390) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeQueryStatement(AbstractLoadPlanBasedLoader.java:163) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:104) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.collection.plan.AbstractLoadPlanBasedCollectionInitializer.initialize(AbstractLoadPlanBasedCollectionInitializer.java:87) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:710) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.internal.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:76) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:99) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.internal.SessionImpl.initializeCollection(SessionImpl.java:2163) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection$4.doWork(AbstractPersistentCollection.java:589) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:264) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:585) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:149) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.PersistentSet.hashCode(PersistentSet.java:458) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at com.examportal.examportalapi.domain.RoleDomain.hashCode(RoleDomain.java:13) ~[classes/:na]
      at com.examportal.examportalapi.domain.UserRoleDomain.hashCode(UserRoleDomain.java:14) ~[classes/:na]
      at java.base/java.util.HashMap.hash(HashMap.java:339) ~[na:na]
      at java.base/java.util.HashMap.put(HashMap.java:607) ~[na:na]
      at java.base/java.util.HashSet.add(HashSet.java:220) ~[na:na]
      at java.base/java.util.AbstractCollection.addAll(AbstractCollection.java:352) ~[na:na]
      at org.hibernate.collection.internal.PersistentSet.endRead(PersistentSet.java:355) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollection(CollectionLoadContext.java:239) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.java:224) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.java:198) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.CollectionReferenceInitializerImpl.endLoading(CollectionReferenceInitializerImpl.java:154) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.finishLoadingCollections(AbstractRowReader.java:253) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.finishUp(AbstractRowReader.java:211) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.ResultSetProcessorImpl.extractResults(ResultSetProcessorImpl.java:96) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:105) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.collection.plan.AbstractLoadPlanBasedCollectionInitializer.initialize(AbstractLoadPlanBasedCollectionInitializer.java:87) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:710) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.internal.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:76) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:99) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.internal.SessionImpl.initializeCollection(SessionImpl.java:2163) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection$4.doWork(AbstractPersistentCollection.java:589) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:264) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:585) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:149) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.PersistentSet.hashCode(PersistentSet.java:458) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at com.examportal.examportalapi.domain.RoleDomain.hashCode(RoleDomain.java:13) ~[classes/:na]
      at com.examportal.examportalapi.domain.UserRoleDomain.hashCode(UserRoleDomain.java:14) ~[classes/:na]
      at java.base/java.util.HashMap.hash(HashMap.java:339) ~[na:na]
      at java.base/java.util.HashMap.put(HashMap.java:607) ~[na:na]
      at java.base/java.util.HashSet.add(HashSet.java:220) ~[na:na]
      at java.base/java.util.AbstractCollection.addAll(AbstractCollection.java:352) ~[na:na]
      at org.hibernate.collection.internal.PersistentSet.endRead(PersistentSet.java:355) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollection(CollectionLoadContext.java:239) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.java:224) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.java:198) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.CollectionReferenceInitializerImpl.endLoading(CollectionReferenceInitializerImpl.java:154) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.finishLoadingCollections(AbstractRowReader.java:253) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.finishUp(AbstractRowReader.java:211) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.ResultSetProcessorImpl.extractResults(ResultSetProcessorImpl.java:96) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:105) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.collection.plan.AbstractLoadPlanBasedCollectionInitializer.initialize(AbstractLoadPlanBasedCollectionInitializer.java:87) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:710) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.internal.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:76) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:99) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.internal.SessionImpl.initializeCollection(SessionImpl.java:2163) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection$4.doWork(AbstractPersistentCollection.java:589) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:264) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:585) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:149) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.PersistentSet.hashCode(PersistentSet.java:458) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at com.examportal.examportalapi.domain.RoleDomain.hashCode(RoleDomain.java:13) ~[classes/:na]
      at com.examportal.examportalapi.domain.UserRoleDomain.hashCode(UserRoleDomain.java:14) ~[classes/:na]
      at java.base/java.util.HashMap.hash(HashMap.java:339) ~[na:na]
      at java.base/java.util.HashMap.put(HashMap.java:607) ~[na:na]
      at java.base/java.util.HashSet.add(HashSet.java:220) ~[na:na]
      at java.base/java.util.AbstractCollection.addAll(AbstractCollection.java:352) ~[na:na]
      at org.hibernate.collection.internal.PersistentSet.endRead(PersistentSet.java:355) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollection(CollectionLoadContext.java:239) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.java:224) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.java:198) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.CollectionReferenceInitializerImpl.endLoading(CollectionReferenceInitializerImpl.java:154) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.finishLoadingCollections(AbstractRowReader.java:253) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.finishUp(AbstractRowReader.java:211) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.ResultSetProcessorImpl.extractResults(ResultSetProcessorImpl.java:96) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:105) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.collection.plan.AbstractLoadPlanBasedCollectionInitializer.initialize(AbstractLoadPlanBasedCollectionInitializer.java:87) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:710) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.internal.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:76) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:99) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.internal.SessionImpl.initializeCollection(SessionImpl.java:2163) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection$4.doWork(AbstractPersistentCollection.java:589) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:264) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:585) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:149) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.PersistentSet.hashCode(PersistentSet.java:458) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at com.examportal.examportalapi.domain.RoleDomain.hashCode(RoleDomain.java:13) ~[classes/:na]
      at com.examportal.examportalapi.domain.UserRoleDomain.hashCode(UserRoleDomain.java:14) ~[classes/:na]
      at java.base/java.util.HashMap.hash(HashMap.java:339) ~[na:na]
      at java.base/java.util.HashMap.put(HashMap.java:607) ~[na:na]
      at java.base/java.util.HashSet.add(HashSet.java:220) ~[na:na]
      at java.base/java.util.AbstractCollection.addAll(AbstractCollection.java:352) ~[na:na]
      at org.hibernate.collection.internal.PersistentSet.endRead(PersistentSet.java:355) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollection(CollectionLoadContext.java:239) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.java:224) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.engine.loading.internal.CollectionLoadContext.endLoadingCollections(CollectionLoadContext.java:198) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.CollectionReferenceInitializerImpl.endLoading(CollectionReferenceInitializerImpl.java:154) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.finishLoadingCollections(AbstractRowReader.java:253) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.finishUp(AbstractRowReader.java:211) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.process.internal.ResultSetProcessorImpl.extractResults(ResultSetProcessorImpl.java:96) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:105) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.loader.collection.plan.AbstractLoadPlanBasedCollectionInitializer.initialize(AbstractLoadPlanBasedCollectionInitializer.java:87) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:710) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.internal.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:76) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:99) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.internal.SessionImpl.initializeCollection(SessionImpl.java:2163) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection$4.doWork(AbstractPersistentCollection.java:589) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:264) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:585) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:149) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at org.hibernate.collection.internal.PersistentSet.hashCode(PersistentSet.java:458) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
      at com.examportal.examportalapi.domain.RoleDomain.hashCode(RoleDomain.java:13) ~[classes/:na]
      at com.examportal.examportalapi.domain.UserRoleDomain.hashCode(UserRoleDomain.java:14) ~[classes/:na]
      at java.base/java.util.HashMap.hash(HashMap.java:339) ~[na:na]
      at java.base/java.util.HashMap.put(HashMap.java:607) ~[na:na]
      at java.base/java.util.HashSet.add(HashSet.java:220) ~[na:na]
  
  </code></pre>