public interface TransactionStatus extends TransactionExecution, SavepointManager, Flushable{
/**
     * Return whether this transaction internally carries a savepoint,
     * that is, has been created as nested transaction based on a savepoint.
     * <p>This method is mainly here for diagnostic purposes, alongside
     * {@link #isNewTransaction()}. For programmatic handling of custom
     * savepoints, use the operations provided by {@link SavepointManager}.
     * @see #isNewTransaction()
     * @see #createSavepoint()
     * @see #rollbackToSavepoint(Object)
     * @see #releaseSavepoint(Object)
     */
boolean hasSavepoint();
Flush the underlying session to the datastore, if applicable: for example, all affected Hibernate/JPA sessions.
This is effectively just a hint and may be a no-op if the underlying transaction manager does not have a flush concept. A flush signal may get applied to the primary resource or to transaction synchronizations, depending on the underlying resource.
@Override
void flush();
}

/**
 * Common representation of the current state of a transaction.
 * Serves as base interface for {@link TransactionStatus} as well as
 * {@link ReactiveTransaction}.
 *
 * @author Juergen Hoeller
 * @since 5.2
 */
public interface TransactionExecution {
    /**
     * Return whether the present transaction is new; otherwise participating
     * in an existing transaction, or potentially not running in an actual
     * transaction in the first place.
     */
    boolean isNewTransaction();
    /**
     * Set the transaction rollback-only. This instructs the transaction manager
     * that the only possible outcome of the transaction may be a rollback, as
     * alternative to throwing an exception which would in turn trigger a rollback.
     */
    void setRollbackOnly();
    /**
     * Return whether the transaction has been marked as rollback-only
     * (either by the application or by the transaction infrastructure).
     */
    boolean isRollbackOnly();
    /**
     * Return whether this transaction is completed, that is,
     * whether it has already been committed or rolled back.
     */
    boolean isCompleted();
}

Object createSavepoint() throws TransactionException;
void rollbackToSavepoint(Object savepoint) throws TransactionException;
void releaseSavepoint(Object savepoint) throws TransactionException;

private boolean rollbackOnly = false;
    private boolean completed = false;
    @Nullable
    private Object savepoint;