Given 2 generic POJOs that include references to each other such as:

package com.example;

public class Course {
    Student _student;

    public void setStudent(Student student) {
      _student = student;
    }

    public Student getStudent() {
      return _student;
    }
}

package com.example;

public class Student {
    private Course _course;

    public void setCourse(Course course) {
      _course = course;
    }
    public Course getCourse() {
      return _course;
    }
}

It would be useful to have a configuration mechanism to prevent Maximum serialization depth exceeded exceptions from being thrown.

package com.example;

import com.mongodb.ConnectionString;
import com.mongodb.MongoClientSettings;
import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoClients;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;

import org.bson.Document;
import org.bson.codecs.configuration.CodecRegistry;
import org.bson.codecs.pojo.PojoCodecProvider;

import static org.bson.codecs.configuration.CodecRegistries.fromProviders;
import static org.bson.codecs.configuration.CodecRegistries.fromRegistries;

public class App {
  public static void main(final String[] args) {
    CodecRegistry pojoCodecRegistry = fromProviders(PojoCodecProvider.builder().automatic(true).build());
    CodecRegistry codecRegistry = fromRegistries(MongoClientSettings.getDefaultCodecRegistry(),
    pojoCodecRegistry);
    MongoClientSettings clientSettings = MongoClientSettings.builder()
    .applyConnectionString(new ConnectionString("mongodb://localhost:27017"))
    .codecRegistry(codecRegistry)
    .build();

    MongoClient mongoClient = MongoClients.create(clientSettings);
        MongoDatabase database = mongoClient.getDatabase("test");

        MongoCollection<Student> students = database.getCollection("students", Student.class);
        MongoCollection<Course> courses = database.getCollection("courses", Course.class);

        students.deleteMany(new Document());
        courses.deleteMany(new Document());

        Student student = new Student();
        Course course = new Course();

        student.setCourse(course);
        course.setStudent(student);

        students.insertOne(student);
        courses.insertOne(course);

        System.out.println(students.find(new Document()).first());
        System.out.println(courses.find(new Document()).first());
  }
}

The above would result in the following:

Exception in thread "main" org.bson.BsonSerializationException: Maximum serialization depth exceeded (does the object being 
serialized have a circular reference?).
        at org.bson.AbstractBsonWriter.writeStartDocument(AbstractBsonWriter.java:285)
        at com.mongodb.internal.connection.BsonWriterDecorator.writeStartDocument(BsonWriterDecorator.java:48)
        at com.mongodb.internal.connection.LevelCountingBsonWriter.writeStartDocument(LevelCountingBsonWriter.java:42)      
        at com.mongodb.internal.connection.IdHoldingBsonWriter.writeStartDocument(IdHoldingBsonWriter.java:78)
        at org.bson.codecs.pojo.PojoCodecImpl.encode(PojoCodecImpl.java:94)
        at org.bson.codecs.pojo.LazyPojoCodec.encode(LazyPojoCodec.java:47)
        at org.bson.codecs.EncoderContext.encodeWithChildContext(EncoderContext.java:91)
        at org.bson.codecs.pojo.PojoCodecImpl.encodeValue(PojoCodecImpl.java:181)
        at org.bson.codecs.pojo.PojoCodecImpl.encodeProperty(PojoCodecImpl.java:169)
        at org.bson.codecs.pojo.PojoCodecImpl.encode(PojoCodecImpl.java:106)
        at org.bson.codecs.pojo.LazyPojoCodec.encode(LazyPojoCodec.java:47)
        at org.bson.codecs.EncoderContext.encodeWithChildContext(EncoderContext.java:91)
....... etc