java.lang.InstantiationException when using inheritance and abstract base class and embedded object

[puneetbehl]

Task List

• Steps to reproduce provided
• Stacktrace (if present) provided
• Example that reproduces the problem uploaded to Github
• Full description of the issue provided (see below)

When using Inheritance from an abstract base class as an embedded object, the list criteria query throws java.lang.InstantiationException.

Steps to Reproduce

1. Create a Grails 4 application.
2. Remove hibernate dependencies and add the Grails MongoDB plugin.
3. Create an abstract base domain class Address as:

abstract class Address {
    String street
}

4. Create another domain class HomeAddress.groovy which implements Address as:

class HomeAddress extends Address {

    String type = "home"
}

5. Create a domain class Patient.groovy which as embedded address as:

class Patient {

    Address address

    static embedded = ['address']
}

6. Try to access list of all patient using following query:

Patient.list()

Expected Behaviour

The query Patient.list() should return all the patients with embedded address information without any error.

Actual Behaviour

The following exception is thrown:

Caused by: java.lang.reflect.UndeclaredThrowableException
	at org.grails.datastore.mapping.core.DatastoreUtils.execute(DatastoreUtils.java:319)
	at org.grails.datastore.gorm.AbstractDatastoreApi.execute(AbstractDatastoreApi.groovy:40)
	at org.grails.datastore.gorm.GormStaticApi.list(GormStaticApi.groovy:607)
	at org.grails.datastore.gorm.GormEntity$Trait$Helper.list(GormEntity.groovy:682)
	... 1 more
Caused by: java.lang.InstantiationException
	at org.grails.datastore.bson.codecs.BsonPersistentEntityCodec.decode(BsonPersistentEntityCodec.groovy:76)
	at org.grails.datastore.bson.codecs.decoders.EmbeddedDecoder.decode(EmbeddedDecoder.groovy:27)
	at org.grails.datastore.bson.codecs.BsonPersistentEntityCodec.decode(BsonPersistentEntityCodec.groovy:121)
	at com.mongodb.operation.CommandResultArrayCodec.decode(CommandResultArrayCodec.java:52)
	at com.mongodb.operation.CommandResultDocumentCodec.readValue(CommandResultDocumentCodec.java:60)
	at org.bson.codecs.BsonDocumentCodec.decode(BsonDocumentCodec.java:84)
	at org.bson.codecs.BsonDocumentCodec.decode(BsonDocumentCodec.java:41)
	at org.bson.codecs.configuration.LazyCodec.decode(LazyCodec.java:47)
	at org.bson.codecs.BsonDocumentCodec.readValue(BsonDocumentCodec.java:101)
	at com.mongodb.operation.CommandResultDocumentCodec.readValue(CommandResultDocumentCodec.java:63)
	at org.bson.codecs.BsonDocumentCodec.decode(BsonDocumentCodec.java:84)
	at org.bson.codecs.BsonDocumentCodec.decode(BsonDocumentCodec.java:41)
	at com.mongodb.internal.connection.ReplyMessage.<init>(ReplyMessage.java:48)
	at com.mongodb.internal.connection.InternalStreamConnection.getCommandResult(InternalStreamConnection.java:393)
	at com.mongodb.internal.connection.InternalStreamConnection.receiveCommandMessageResponse(InternalStreamConnection.java:299)
	at com.mongodb.internal.connection.InternalStreamConnection.sendAndReceive(InternalStreamConnection.java:255)
	at com.mongodb.internal.connection.UsageTrackingInternalConnection.sendAndReceive(UsageTrackingInternalConnection.java:99)
	at com.mongodb.internal.connection.DefaultConnectionPool$PooledConnection.sendAndReceive(DefaultConnectionPool.java:444)
	at com.mongodb.internal.connection.CommandProtocolImpl.execute(CommandProtocolImpl.java:72)
	at com.mongodb.internal.connection.DefaultServer$DefaultServerProtocolExecutor.execute(DefaultServer.java:200)
	at com.mongodb.internal.connection.DefaultServerConnection.executeProtocol(DefaultServerConnection.java:269)
	at com.mongodb.internal.connection.DefaultServerConnection.command(DefaultServerConnection.java:131)
	at com.mongodb.internal.connection.DefaultServerConnection.command(DefaultServerConnection.java:123)
	at com.mongodb.operation.CommandOperationHelper.executeWrappedCommandProtocol(CommandOperationHelper.java:242)
	at com.mongodb.operation.CommandOperationHelper.executeWrappedCommandProtocol(CommandOperationHelper.java:233)
	at com.mongodb.operation.CommandOperationHelper.executeWrappedCommandProtocol(CommandOperationHelper.java:136)
	at com.mongodb.operation.FindOperation$1.call(FindOperation.java:701)
	at com.mongodb.operation.FindOperation$1.call(FindOperation.java:695)
	at com.mongodb.operation.OperationHelper.withConnectionSource(OperationHelper.java:462)
	at com.mongodb.operation.OperationHelper.withConnection(OperationHelper.java:406)
	at com.mongodb.operation.FindOperation.execute(FindOperation.java:695)
	at com.mongodb.operation.FindOperation.execute(FindOperation.java:83)
	at com.mongodb.client.internal.MongoClientDelegate$DelegateOperationExecutor.execute(MongoClientDelegate.java:179)
	at com.mongodb.client.internal.MongoIterableImpl.execute(MongoIterableImpl.java:132)
	at com.mongodb.client.internal.MongoIterableImpl.iterator(MongoIterableImpl.java:86)
	at org.grails.datastore.mapping.mongo.query.MongoQuery.executeQuery(MongoQuery.java:527)
	at org.grails.datastore.mapping.mongo.query.MongoQuery.executeQuery(MongoQuery.java:464)
	at org.grails.datastore.mapping.query.Query.doList(Query.java:589)
	at org.grails.datastore.mapping.query.Query.list(Query.java:568)
	at org.grails.datastore.gorm.GormStaticApi.list_closure20(GormStaticApi.groovy:608)
	at groovy.lang.Closure.call(Closure.java:405)
	... 5 more

Environment Information

• Operating System: macOS
• Grails Version: 4.0.3
• JDK Version: 1.8.hs-adpt
• Container Version (If Applicable): MongoDB 3 Docker Image

Example Application

• https://github.com/puneetbehl/mongodbdemo/tree/abstractEmbeddedMongo