Mongo DB query in java

问题

I have to write a complex mongo query using java but am not able to do it.

The mongo query looks like this:

db.video.findOne( { 
    $or: [ 
        { key1: { $in : [764] } }, 
        { key2: {$in : [list2] } }, 
        { $and [ { key2 : 3}, {key4:67} ] } 
    ]
})

I have to write the above query using the QueryBuilder class. In what way can I do it?

Thanks

回答1:

Using QueryBuilder your query should look like this

DBObject query = QueryBuilder.start().or(
    QueryBuilder.start("key1").in(764).get(),
    QueryBuilder.start("key2").in(keys).get(),
    QueryBuilder.start().and("key3").is(3).and("key4").is(64).get()
 ).get();

Consider using jongo (an API over mongo-java-driver) you can simply copy/paste queries from the shell :

collection.findOne("{$or:[{key1: {$in:[764]}},{key2:{$in:[#]}}, {$and:[{key3:3},{key4:67}]}]}", keys).as(People.class);

回答2:

I had the same problem and i got a solution in another way :

ArrayList orList = new ArrayList();
ArrayList andList = new ArrayList();

orList.add(new BasicDBObject("key1", new BasicDBObject("$in", 764)));                  
orList.add(new BasicDBObject("key2", new BasicDBObject("$in", list2)));

andList.add(new BasicDBObject("key2", 3));
andList.add(new BasicDBObject("key4", 67));

orList.add(new BasicDBObject("$and", andList));

BasicDBObject query = new BasicDBObject("$or", orList);

来源：https://stackoverflow.com/questions/10444038/mongo-db-query-in-java