code: @NotNull
      protected final JpaStream findStream(@NotNull final StreamId streamId) {
  
          Contract.requireArgNotNull("streamId", streamId);
          verifyStreamEntityExists(streamId);
  
          final String sql = createJpqlStreamSelect(streamId);
          final TypedQuery<JpaStream> query = getEm().createQuery(sql, JpaStream.class);
          setJpqlParameters(query, streamId);
          final List<JpaStream> streams = query.getResultList();
          if (streams.size() == 0) {
              throw new StreamNotFoundException(streamId);
          }
          final JpaStream stream = streams.get(0);
          if (stream.getState() == StreamState.SOFT_DELETED) {
              // TODO Remove after event store has a way to distinguish between
              // never-existing and soft deleted
              // streams
              throw new StreamNotFoundException(streamId);
          }
          return stream;
  
      }
docs: Reads the stream with the given identifier from the DB and returns it.
  
  @param streamId
  Stream to load.
  
  @return Stream.