Unable to make private fields accessible - while migrating to springboot3.2.0, Java21

While trying to migrate my application from Java8,Springboot v1.x to Java21,Springboot v3.2.0, I encountered the following issue while trying to configure cassandra in my application:

> Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'cassandraMappingContext' defined in class path resource [com/blabla/main/CassandraConfig.class]: Unable to make field private long java.util.GregorianCalendar.gregorianCutover accessible: module java.base does not "opens java.util" to unnamed module @61862a7f
> at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1775)
> at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:601)
> at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:523)
> at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:325)
> at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
> at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:323)
> at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:224)
> at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveNamedBean(DefaultListableBeanFactory.java:1321)
> at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveNamedBean(DefaultListableBeanFactory.java:1282)
> at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveBean(DefaultListableBeanFactory.java:484)
> at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:339)
> at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:332)
> at org.springframework.data.cassandra.config.AbstractSessionConfiguration.requireBeanOfType(AbstractSessionConfiguration.java:103)
> at org.springframework.data.cassandra.config.AbstractCassandraConfiguration.cassandraConverter(AbstractCassandraConfiguration.java:76)
> at com.blabla.main.CassandraConfig$$SpringCGLIB$$0.CGLIB$cassandraConverter$20(<generated>)
> at com.blabla.main.CassandraConfig$$SpringCGLIB$$FastClass$$0.invoke(<generated>)
> at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:258)
> at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:331)
> at com.blabla.main.CassandraConfig$$SpringCGLIB$$0.cassandraConverter(<generated>)
> at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
> at java.base/java.lang.reflect.Method.invoke(Method.java:580)
> at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:140)
> 142 common frames omitted
> Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make field private long java.util.GregorianCalendar.gregorianCutover accessible: module java.base does not "opens java.util" to unnamed module @61862a7f
> at java.base/java.lang.reflect.AccessibleObject.throwInaccessibleObjectException(AccessibleObject.java:391)
> at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:367)
> at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:315)
> at java.base/java.lang.reflect.Field.checkCanSetAccessible(Field.java:183)
> at java.base/java.lang.reflect.Field.setAccessible(Field.java:177)
> at org.springframework.util.ReflectionUtils.makeAccessible(ReflectionUtils.java:804)
> at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.doWith(AbstractMappingContext.java:616)
> at org.springframework.util.ReflectionUtils.doWithFields(ReflectionUtils.java:728)
> at org.springframework.data.mapping.context.AbstractMappingContext.doAddPersistentEntity(AbstractMappingContext.java:471)
> at org.springframework.data.mapping.context.AbstractMappingContext.addPersistentEntity(AbstractMappingContext.java:424)
> at org.springframework.data.cassandra.core.mapping.CassandraMappingContext.addPersistentEntity(CassandraMappingContext.java:326)
> at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.lambda$createAndRegisterProperty$3(AbstractMappingContext.java:671)
> at java.base/java.lang.Iterable.forEach(Iterable.java:75)
> at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.createAndRegisterProperty(AbstractMappingContext.java:668)
> at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.doWith(AbstractMappingContext.java:622)
> at org.springframework.util.ReflectionUtils.doWithFields(ReflectionUtils.java:728)
> at org.springframework.data.mapping.context.AbstractMappingContext.doAddPersistentEntity(AbstractMappingContext.java:471)
> at org.springframework.data.mapping.context.AbstractMappingContext.addPersistentEntity(AbstractMappingContext.java:424)
> at org.springframework.data.cassandra.core.mapping.CassandraMappingContext.addPersistentEntity(CassandraMappingContext.java:326)
> at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.lambda$createAndRegisterProperty$3(AbstractMappingContext.java:671)
> at java.base/java.lang.Iterable.forEach(Iterable.java:75)
> at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.createAndRegisterProperty(AbstractMappingContext.java:668)
> at org.springframework.data.mapping.context.AbstractMappingContext$PersistentPropertyCreator.doWith(AbstractMappingContext.java:622)
> at org.springframework.util.ReflectionUtils.doWithFields(ReflectionUtils.java:728)
> at org.springframework.data.mapping.context.AbstractMappingContext.doAddPersistentEntity(AbstractMappingContext.java:471)
> at org.springframework.data.mapping.context.AbstractMappingContext.addPersistentEntity(AbstractMappingContext.java:424)
> at org.springframework.data.cassandra.core.mapping.CassandraMappingContext.addPersistentEntity(CassandraMappingContext.java:326)
> at org.springframework.data.mapping.context.AbstractMappingContext.addPersistentEntity(AbstractMappingContext.java:384)
> at java.base/java.lang.Iterable.forEach(Iterable.java:75)
> at org.springframework.data.cassandra.CassandraManagedTypes.forEach(CassandraManagedTypes.java:81)
> at org.springframework.data.mapping.context.AbstractMappingContext.initialize(AbstractMappingContext.java:563)
> at org.springframework.data.cassandra.core.mapping.CassandraMappingContext.initialize(CassandraMappingContext.java:114)
> at org.springframework.data.mapping.context.AbstractMappingContext.afterPropertiesSet(AbstractMappingContext.java:555)
> at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1822)
> at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1771)
> 163 common frames omitted

The CassandraConfig.java implementation:

@Configuration
@EnableCassandraRepositories(basePackages = "com.blabla")
public class CassandraConfig extends AbstractCassandraConfiguration {

  @Value("${cassandra.contactpoints}")
  private String contactPoints;

  @Value("${cassandra.port}")
  private int port;

  @Value("${cassandra.keyspace}")
  private String keySpace;

  @Value("${cassandra.basePackages}")
  private String basePackages;

  @Value("${cassandra.cluster}")
  private String clusterName;

  @Value("${cassandra.username}")
  private String username;
  
  @Value("${cassandra.consistency}")
  private String consistency;

  private String password;

  private static final Logger log = LoggerFactory.getLogger(CassandraConfig.class);

  @PostConstruct
  public void init(){
    // logic to get my password to connect with cassandra from another repo.
  }

  protected AuthProvider getAuthProvider() {
    return new PlainTextAuthProvider(username, password);
  }

  @Override
  protected String getKeyspaceName() {
    return keySpace;
  }

  @Override
  protected String getContactPoints() {
    return contactPoints;
  }

  @Override
  protected int getPort() {
    return port;
  }

  @Override
  public SchemaAction getSchemaAction() {
    return SchemaAction.CREATE_IF_NOT_EXISTS;
  }

  @Override
  public String[] getEntityBasePackages() {
    return new String[] {basePackages};
  }

  @Override
  protected String getClusterName() {
    return clusterName;
  }

  @Bean
  public QueryLogger queryLogger(Cluster cluster) {
    QueryLogger queryLogger = QueryLogger.builder().build();
    cluster.register(queryLogger);
    return queryLogger;
  }

  protected AddressTranslator getAddressTranslator() {
    return new CassandraAddressTranslator();
  }
  
  protected QueryOptions getQueryOptions() {
    QueryOptions queryOptions = new QueryOptions();
    queryOptions.setConsistencyLevel(ConsistencyLevel.valueOf(consistency));
    return queryOptions;
  }

}

I am using the following dependency for cassandra:

<dependency>
    <groupId>org.springframework.data</groupId>
    <artifactId>spring-data-cassandra</artifactId>
    <version>4.3.3</version>
 </dependency>

I am unable to find the solution how my code can access the private field gregorianCutover from class GregorianCalendar.

At a number of places, I found a solution to use the following JVM arguments:

java --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.lang.reflect=ALL-UNNAMED --add-opens=java.base/java.io=ALL-UNNAMED

But I also got to know that this is not a safe and advisable approach to be followed.

Can someone please suggest a safe and clean approach to handle this issue?

I am using the latest version of all the dependencies.