how to execute mongo admin command from java

Question

I want to execute soem admin command with parameters from java.

The commands are:

{ enablesharding : "test" }
{ shardcollection : "test.test_collection", key : {"number":1} }

How can I do it from java driver?

The following code doesn't works:

mongo.getDb("admin").command("{shardcollection : \"test.test_collection\", key:\"number\":1} }")

Deaf

Answer 1

I just found it

DB db = mongo.getDB("admin");
DBObject cmd = new BasicDBObject();
cmd.put("shardcollection", "testDB.x");
cmd.put("key", new BasicDBObject("userId", 1));
CommandResult result = db.command(cmd);

Deaf

This answer was useful for me. I'll just point that I needed to connect to a mongos, a simple mongod is not enough. It may be obvious but I didn't saw it here explicitly. – Omentum

mongo.getDb("admin").runCommand would have been more intuitive. – Parliamentarian

Answer 2

I just want to add that Julias's answer is correct, but now it's deprecated. You could use new API (Document class is from package org.bson):

MongoDatabase database = client.getDatabase("admin");
Document documentA = database.runCommand(new Document("enablesharding", "test"));
Document documentB = database.runCommand(
        new Document("shardcollection", "testDB.x").append("key", new Document("userId", 1)));

Tang

How can you tell if the return Document was successful or not? The CommandResult has an OK method on it. Document does not – Anette

Answer 3

Have you ensured you have authenticated to the db successfully?

Have you tried db.eval(COMMAND_THAT_YOU_WANT_TO_EVAL);

Trixy

db.eval() has two arguments. I do not know what Objects... args should be – Deaf

You might want to take a closer look @Julias. The second argument is a variable length argument list; this means is can be zero or more arguments. – Trixy

Keep in mind this does not work in sharded environments – Eurasian