com.hangum.tadpole.mongodb.core.test.MongoTestGroup.java Source code

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Here is the source code for com.hangum.tadpole.mongodb.core.test.MongoTestGroup.java

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/*******************************************************************************
 * Copyright (c) 2013 hangum.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the GNU Lesser Public License v2.1
 * which accompanies this distribution, and is available at
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * 
 * Contributors:
 *     hangum - initial API and implementation
 ******************************************************************************/
package com.hangum.tadpole.mongodb.core.test;

import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBObject;
import com.mongodb.Mongo;
import com.mongodb.util.JSON;

/**
 * MongoDB Group example
 * 
 * http://greenfishblog.tistory.com/105 ? group 
 * 
{"dep_id":1, "salary":1}
{"dep_id":1, "salary":2}
{"dep_id":1, "salary":3}
{"dep_id":2, "salary":10}
{"dep_id":2, "salary":12}
{"dep_id":2, "salary":16}
{"dep_id":3, "salary":4}
{"dep_id":3, "salary":1}
 * 
 * @author hangum
 * 
 */
public class MongoTestGroup {

    static String key = "";//{ dep_id : true}";
    static String initial = "{sum_salary:0,avg:0,cnt:0}";

    static String condition = "";//"{dep_id : { $gt : 2 }}";

    static String reduce = "function(obj,prev){prev.sum_salary += obj.salary;prev.cnt++;}";

    static String finalizer = "function(out){out.avg=out.sum_salary / out.cnt;}";

    /**
     * @param args
     */
    public static void main(String[] args) throws Exception {

        ConAndAuthentication testMongoCls = new ConAndAuthentication();
        Mongo mongo = testMongoCls.connection(ConAndAuthentication.serverurl, ConAndAuthentication.port);
        DB db = mongo.getDB("test");
        DBCollection coll = db.getCollection("group");

        DBObject dbObjectKey = (DBObject) JSON.parse(key);
        DBObject dbObjectInitial = (DBObject) JSON.parse(initial);
        DBObject dbObjectCondition = (DBObject) JSON.parse(condition);

        DBObject resultDBObject = coll.group(dbObjectKey, dbObjectCondition, dbObjectInitial, reduce, finalizer);
        System.out.println(resultDBObject);

        mongo.close();

        try {
            Thread.sleep(1);
        } catch (Exception e) {
        }
    }
}