Using lambda function in MongoDB $where clause in Java

Question

I'm trying to execute JavaScript equivalent query in Java using the $where clause. The JavaScript query looks like this:

var currDate = new ISODate()
db.getCollection('rides')
.find(
{
        "startDate" : {
            "$lte" : currDate
        },
        "stopDate" : {
            "$gte" : currDate
         },
        $where : function() { return (this.weekday == new Date(new ISODate().getTime() + this.timeOffset).getDay()) }
}
)

While weekday and timeOffset are document fields. This query works just fine in MongoDB shell. I'm trying to find out a way to write this query in Java 8. I've tried the following:

BasicDBObject query =  new BasicDBObject("stopDate",new BasicDBObject("$gte", currDate))
                .append("startDate",new BasicDBObject("$lte", currDate))
                .append("weekday",
                        new BasicDBObject("$where", () ->
                        {
                            return (this.weekday == currDate + this.timeOffset)
                        }));

However I can't even compile this code. Java this is not recognized. Is there a way to accomplish the query in Java?

Thanks in advance for help!

Valeriy · Accepted Answer · 2015-07-30 19:51:51Z

1

Ok,

I've figured out an alternative solution for the same query. Since the following Javascript query is equivalent to the posted one:

var currDate = new ISODate()
db.getCollection('rides')
.find(
{
    "startDate" : {
        "$lte" : currDate
    },
    "stopDate" : {
        "$gte" : currDate
     },
    $where : 'this.weekday == new Date(new Date().getTime() + this.timeOffset).getDay()'
})

I could just write the same in Java:

BasicDBObject query =  new BasicDBObject("stopDate",new BasicDBObject("$gte", currDate))
            .append("startDate", new BasicDBObject("$lte", currDate))
            .append("$where", "this.weekday == new Date(new Date().getTime() + this.timeOffset).getDay()");

And it perfectly worked for me!

answered Jul 30, 2015 at 19:51

Valeriy

312 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

蒋明涛 · Accepted Answer · 2019-03-20 05:28:03Z

0

Document whereDoc = new Document(
    "$where",
    "function(){var j=false; [2,4].forEach(i=>{if([4,5].indexOf(i)>-1){j=true;}}); return j;}"
);

Query query = new BasicQuery(whereDoc);
query.addCriteria(Criteria.where("ent_id").is("google"));
query.addCriteria(Criteria.where("app_id").is("pic"));
List<Map> result = mongoTemplate.find(query, Map.class, "googletest");

answered Mar 20, 2019 at 5:28

蒋明涛

1

1 Comment

Scotty Waggoner Over a year ago

Answers are usually more helpful if you can explain what you did and why instead of just pasting a wall of code. Also this doesn't really look like the query that was asked about (there are no dates and other fields are being queried on).

Collectives™ on Stack Overflow

Using lambda function in MongoDB $where clause in Java

2 Answers 2

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related