使用ObjectId的字符串表示形式搜索mongo文档

Question

I am trying to return the a document using the string representation of its id (ObjectId) from a java class using Morphia. How can I achieve this? The following code snippett illustrates the problem...

    @Override
public List<SmsReply> getReplies() {
    List<SmsReply> replies = smsProvider.getSmsReplies();
    for(SmsReply reply: replies){
        System.out.println(reply);
        Sms sms = datastore.find(Sms.class, "_id", reply.getExternalMessageId()).get();
        sms.getSmsReplies().add(reply);
        datastore.save(sms);
    }

    return smsProvider.getSmsReplies();
}

The SmsReply class has a string representation of the ObjectId (externalMessageId) of the Sms document that it needs to find.

Thanks for your help.

Answer 1

如果_id是mongo中的ObjectId，则可以使用ObjectId上的String构造函数创建一个ObjectId实例java：new ObjectId（reply.getExternalMessageId（））