RequestHandler.java Source code

Introduction

Here is the source code for RequestHandler.java
Source

import com.mongodb.MongoClient;

import com.mongodb.MongoException;
import com.mongodb.WriteConcern;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.BasicDBObject;
import com.mongodb.DBObject;
import com.mongodb.DBCursor;
import com.mongodb.ServerAddress;
import com.mongodb.client.FindIterable;
import com.mongodb.Block;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import javax.json.JsonObject;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author Alankritha
 */
public class RequestHandler {
    private static final MongoClient mongo = new MongoClient("localhost", 27017);

    protected String collection; // == craigslist_users
    protected HashMap<String, String> document = new HashMap<>();

    protected RequestHandler(String collection) {
        this.collection = collection;

    }

    public void insert(HttpServletRequest request) {
        DB db = mongo.getDB("test");
        DBCollection dbc = db.getCollection(collection);
        BasicDBObject add = new BasicDBObject();

        for (Map.Entry<String, String> ent : this.document.entrySet()) {
            add.append(ent.getKey(), request.getParameter(ent.getValue()));
        }
        dbc.insert(add);
        System.out.print(add);

    }

    public void retrieve(HttpServletRequest request, HttpServletResponse response) {
        DB db = mongo.getDB("test");
        DBCollection dbc = db.getCollection(collection);
        BasicDBObject add = new BasicDBObject();

        try (PrintWriter out = response.getWriter()) {
            /*TODO output your page here. You may use following sample code. */
            out.println("<!DOCTYPE html>");
            out.println("<html>");
            out.println("<head><script>" + "function myFunction(elt) {"
                    + " elt.setAttribute('selected_object_id', elt.getAttribute('id'));"
                    + "var xhr = new XMLHttpRequest();"
                    + "    xhr.open('GET', 'http://localhost:8080/MongoCraig/DeleteInfo', true);"
                    + "    xhr.send(null);}" + "</script></head>");
            DBCursor cursor = dbc.find();
            out.println("<body>");
            for (DBObject record : cursor) {
                out.println("<p>First Name : " + record.get("firstname") + "</p>");
                out.println("<p>Last Name : " + record.get("lastname") + "</p>");
                out.println("<p>What : " + record.get("what") + "</p>");
                out.println("<p>Price : " + record.get("price") + "</p>");
                out.println("<button id=" + record.get("_id") + " onclick='myFunction(this); '>DELETE</button> ");

            }
            out.println("</body>");
            out.println("</html>");
        } catch (Exception e) {

        }
    }

    public void delete(HttpServletRequest request, HttpServletResponse response) {
        DB db = mongo.getDB("test");
        DBCollection dbc = db.getCollection(collection);
        BasicDBObject add = new BasicDBObject();
        try {
            PrintWriter out = response.getWriter();
            out.println(request.getParameter("selected_object_id"));
        } catch (Exception e) {

        }
        System.out.println(request.getParameter("selected_object_id"));
        add.put("_id", request.getParameter("selected_object_id"));
        dbc.remove(add);
        retrieve(request, response);

    }
}