Read/Write Large Byte Array

I need to write and read a byte array to and from MongoDB. In Java, the data is in a form of

public class RawData{

    private String id;

    private byte[] data;


The byte array can be long enough to exhaust all available memory. One (easy ?) solution is to cut a long byte array into a few pieces and store them one by one. Any features of MongoDB can be used for this scenario? I am thinking of reactive for some reason.