In the Java Mongo DB driver version 3 the API has changed as compared to the version 2. So a code like this does not compile anymore:
BasicDBObject personObj = new BasicDBObject();
collection.insert(personObj)
A Collection insert works only with a Mongo Document.
Dealing with the old code I need to ask the question:
What is the best way to convert a BasicDBObject to a Document?
We Can Convert BasicDBObject
to Document by the following way
public static Document getDocument(DBObject doc)
{
if(doc == null) return null;
return new Document(doc.toMap());
}
as Document itself is an implementation of Map<String,Object>.
and BasicDBObject can be too be catch in DBObject as BasicDBObject is an implementation of DBObject.
@Black_Rider for you too
I think the easiest thing to do is just change your code to use a Document as opposed to BasicDBObject.
So change
BasicDBObject doc = new BasicDBObject("name", "john")
.append("age", 35)
.append("kids", kids)
.append("info", new BasicDBObject("email", "[email protected]")
.append("phone", "876-134-667"));
To
import org.bson.Document;
...
Document doc = new Document("name", "john")
.append("age", 35)
.append("kids", kids)
.append("info", new BasicDBObject("email", "[email protected]")
.append("phone", "876-134-667"));
and then insert into the collection
coll.insertOne(doc);
You'll need to change other bits of code to work with MongoDB 3+
MongoDatabase vs. DB MongoCollection vs DBCollection
The Document is very similar to the BasicDBObject. I am not quite sure what you are referring to as a way to convert BasicDBObjects to Documents, but the Document object provides some very useful methods.
Document.parse(string) will return a Document if you feed it in a JSON string.
Document.append("key", Value) will add to the fields of a Document.
As for the code in your post, this should compile with version 3:
Document personObj = new Document();
collection.insertOne(personObj)
See
and
@SuppressWarnings("unchecked")
public static Document getDocument(BasicDBObject doc)
{
if(doc == null) return null;
Map<String, Object> originalMap = doc.toMap();
Map<String, Object> resultMap = new HashMap<>(doc.size());
for(Entry<String, Object> entry : originalMap.entrySet())
{
String key = entry.getKey();
Object value = entry.getValue();
if(value == null)
{
continue;
}
if(value instanceof BasicDBObject)
{
value = getDocument((BasicDBObject)value);
}
if(value instanceof List<?>)
{
List<?> list = (List<?>) value;
if(list.size() > 0)
{
// check instance of first element
Object firstElement = list.get(0);
if(firstElement instanceof BasicDBObject)
{
List<Document> resultList = new ArrayList<>(list.size());
for(Object listElement : list)
{
resultList.add(getDocument((BasicDBObject)listElement));
}
value = resultList;
}
else
{
value = list;
}
}
}
resultMap.put(key, value);
}
Document result = new Document(resultMap);
return result;
}
