没有在MongoDB[ANDROID]中进行插入

我正在尝试将数据从Android应用程序插入MongoDB。为此，我编写了这段代码（如下所示），但在执行insert任务时，这段代码不起任何作用。此代码既不会给出任何错误或异常，也不会向数据库插入数据。那么问题是什么？我如何解决这个问题

在SetNotification.java中，我执行以下操作：

Task save_task = new Task();
save_task.date = showDate.getText().toString();
save_task.location = showLocation.getText().toString();
save_task.description = note.getText().toString();

SaveAsyncTask tsk = new SaveAsyncTask(SetNotification.this);
tsk.execute(save_task);

这是SaveAsyncTask.jav一个类：

package com.example.abc.project1.MongoHQ;

/**
 * Created by abc on 02-May-16.
 */
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;

import android.content.Context;
import android.os.AsyncTask;
import android.util.Log;
import android.widget.Toast;

import com.example.abc.project1.SetNotification;
import com.example.abc.project1.Task;

public class SaveAsyncTask extends AsyncTask<Task, Void, Boolean> {

    private static Context context;
    public SaveAsyncTask(Context c) {
        context = c;
    }


    @Override
    protected Boolean doInBackground(Task... arg0) {
        try
        {
            Task task = arg0[0];

            QueryBuilder qb = new QueryBuilder();

            HttpClient httpClient = new DefaultHttpClient();
            HttpPost request = new HttpPost(qb.buildContactsSaveURL());

            StringEntity params =new StringEntity(qb.createTask(task));
            request.addHeader("content-type", "application/json");
            request.setEntity(params);
            HttpResponse response = httpClient.execute(request);

            if(response.getStatusLine().getStatusCode()<205)
            {
                Toast.makeText(context, "SAVED", Toast.LENGTH_SHORT).show();
                return true;
            }
            else
            {
                Toast.makeText(context, "Saving failed", Toast.LENGTH_SHORT).show();
                return false;
            }
        } catch (Exception e) {
            //Log.e("MYAPP", "exception",e);
            e.printStackTrace();
            return false;
        }
    }

}

package com.example.abc.project1.MongoHQ;

import com.example.abc.project1.Task;

/**
 * Created by abc on 02-May-16.
 */

public class QueryBuilder {

    /**
     * Specify your database name here
     * @return
     */
    public String getDatabaseName() {
        return "location_notification";
    }

    /**
     * Specify your MongoLab API here
     * @return
     */
    public String getApiKey() {
        return "################################";
    }

    /**
     * This constructs the URL that allows you to manage your database,
     * collections and documents
     * @return
     */
    public String getBaseUrl()
    {
        return "https://api.mongolab.com/api/1/databases/"+getDatabaseName()+"/collections/";
    }

    /**
     * Completes the formating of your URL and adds your API key at the end
     * @return
     */
    public String docApiKeyUrl()
    {
        return "?apiKey="+getApiKey();
    }

    /**
     * Returns the docs101 collection
     * @return
     */
    public String documentRequest()
    {
        return "tasks";
    }

    /**
     * Builds a complete URL using the methods specified above
     * @return
     */
    public String buildContactsSaveURL()
    {
        return getBaseUrl()+documentRequest()+docApiKeyUrl();
    }

    /**
     * Formats the contact details for MongoHQ Posting
     * @param : Details of the person
     * @return
     */
    public String createTask(Task task)
    {
        return String
                .format("{\"document\"  : {\"date\": \"%s\", "
                                + "\"location\": \"%s\", \"description\": \"%s\"}, \"safe\" : true}",
                        task.date, task.location, task.description);
    }



}