Mongodb: `com.mongodb.MongoSocketReadException: Prematurely reached end of stream` with morphia

Most of the time this is a result of timeouts with long reads\writes.

try to increase the timeouts or remove them completely:

    MongoClientOptions.Builder options_builder = new MongoClientOptions.Builder();
    options_builder.maxConnectionIdleTime(<some_long_time>);
    MongoClientOptions options = options_builder.build();
    MongoClient mongo_db = new MongoClient ("your.db.address", options);

I don't have the root cause, but in the end I get the issue fixed by changing a field type from BigDecimal to double.

The issue is found in our SIT environmet and one developer's windows environment which has a mongodb cluser setup.

The most likely reason is the compatibility version is set too low.

Try db.adminCommand( { setFeatureCompatibilityVersion: "3.4" } )

https://docs.mongodb.com/manual/reference/command/setFeatureCompatibilityVersion/