mongodb.sortDocument.java Source code

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Here is the source code for mongodb.sortDocument.java

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/*
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//
//Sorting Documents Represented by a Cursor in Java.
//
package mongodb;

import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.MongoClient;

/**
 *
 * @author soham
 */
public class sortDocument {
    public static void main(String[] args) {
        try {
            MongoClient mongoClient = new MongoClient("localhost", 27017);
            DB db = mongoClient.getDB("words");
            DBCollection collection = db.getCollection("word_stats");
            sortDocument.sortWordsAscending(collection);
            sortDocument.sortWordsDesc(collection);
            sortDocument.sortWordsAscAndSize(collection);
        } catch (Exception e) {
            System.out.println(e);
        }
    }

    public static void displayCursor(DBCursor cursor) {
        String words = "";
        while (cursor.hasNext()) {
            DBObject doc = cursor.next();
            words = words.concat(doc.get("word").toString()).concat(",");
        }
        if (words.length() > 65) {
            words = words.substring(0, 65) + "...";
        }
        System.out.println(words);
    }

    public static void sortWordsAscending(DBCollection collection) {
        BasicDBObject query = new BasicDBObject("first", "w");
        DBCursor cursor = collection.find(query);
        BasicDBObject sorter = new BasicDBObject("word", 1);
        cursor.sort(sorter);
        System.out.println("\nW words ordered ascending: ");
        sortDocument.displayCursor(cursor);
    }

    public static void sortWordsDesc(DBCollection collection) {
        BasicDBObject query = new BasicDBObject("first", "w");
        DBCursor cursor = collection.find(query);
        BasicDBObject sorter = new BasicDBObject("word", -1);
        cursor.sort(sorter);
        System.out.println("\nW words ordered descending: ");
        sortDocument.displayCursor(cursor);
    }

    public static void sortWordsAscAndSize(DBCollection collection) {
        BasicDBObject query = new BasicDBObject("first", "q");
        DBCursor cursor = collection.find(query);
        BasicDBObject sorter = new BasicDBObject("last", 1);
        sorter.append("size", -1);
        cursor.sort(sorter);
        System.out.println("\nQ words ordered first by last letter " + "and then by size: ");
        sortDocument.displayCursor(cursor);
    }

}