Easy life with Spring Data Mongodb Criteria

Posted By : Prabjot Singh | 07-Jun-2015

mongodb

Mongodb is famous for ignoring table joins,so we can save document inside other document called embedded document. I saw many people confuse about how to queries on embedded document. So I will show you how can easily you can update delete embedded document using mongotemplate. for this I will use mongotemplate query,because I am more comfortable with mongotemplate.

I am considering you know about how to configure spring data mongodb in project. If you don't know you can find at my blog Configure Spring Data Mongodb

So my domain design looks like

public class Metadata extends BaseEntity { 

	private MetadataEnum preferenceType; 
	 
	List subtypes = new ArrayList(); 

	public MetadataEnum getPreferenceType() { 
		return preferenceType; 
	} 

	public void setPreferenceType(MetadataEnum preferenceType) { 
		this.preferenceType = preferenceType; 
	} 

	public List getSubtypes() { 
		return subtypes; 
	} 

	public void setSubtypes(List subtypes) { 
		this.subtypes = subtypes; 
	}  
}

and my database looks like

 { 
	"_id" : ObjectId("556d5853e4b0c91c189d7e02"), 
	"_class" : "com.samepinch.domain.metadata.Metadata", 
	"preferenceType" : “food”, 
	"username" : "[email protected]",
	“subtypes”:[{
		"_id" : ObjectId("556d5853e4b0c91c189d7e03"), 
		“type”:”burger”
	}]
}

There,my subdocument is subtypes,so I will perofrm operations on subtype document which in embedded in users collection.

Update Embedded document

Here I will update type of subtypes using mongotemplate criteria.

Query query = new Query(Criteria.where("id").is(new ObjectId(“556d5853e4b0c91c189d7e02”)) 
				.and("subtypes.id").is(new ObjectId(“556d5853e4b0c91c189d7e03”))); 
		Update update = new Update.update("preferenceType", 
				metadata.getPreferenceType()); 
		update.set("subtypes.$.type ",”noodles”); 
		mongoTemplate.updateFirst(query, update, Metadata.class);

Delete Embedded document

 Query query = new Query(Criteria.where("subtypes").elemMatch( 
				Criteria.where("_id").is(new ObjectId(“556d5853e4b0c91c189d7e03”)))); 
		Update update = new Update().pull("subtypes", 
				new Query(Criteria.where("_id").is(new ObjectId(“556d5853e4b0c91c189d7e03”)))); 
		mongoTemplate.updateMulti(query, update, Metadata.class);

Thanks !!!