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To retrieve the first document in a collection, you can use findOne(). Following is the syntaxvar anyVariableName=db.yourCollectionName.findOne(); //To print result at MongoDB console write the variable name yourVariableNameLet us first create a collection with documents> db.retrieveFirstDocumentDemo.insertOne({"ClientName":"Robert", "ClientAge":23}); { "acknowledged" : true, "insertedId" : ObjectId("5ca2325966324ffac2a7dc6d") } > db.retrieveFirstDocumentDemo.insertOne({"ClientName":"Chris", "ClientAge":26}); { "acknowledged" : true, "insertedId" : ObjectId("5ca2326266324ffac2a7dc6e") } > db.retrieveFirstDocumentDemo.insertOne({"ClientName":"Larry", "ClientAge":29}); { "acknowledged" : true, "insertedId" : ObjectId("5ca2326a66324ffac2a7dc6f") } > db.retrieveFirstDocumentDemo.insertOne({"ClientName":"David", "ClientAge":39}); { "acknowledged" : true, "insertedId" : ObjectId("5ca2327566324ffac2a7dc70") }Following is the query to display all documents from a collection with the help of ... Read More
Let’s say the following is our Collection i.e. ArrayList −Listlist = new ArrayList(); list.add(100); list.add(200); list.add(200); list.add(200); list.add(300); list.add(400); list.add(400); list.add(500);Now, create another Collection −List list2 = new ArrayList(); list2.add(100); list2.add(200); list2.add(300); list2.add(400);To remove all elements from a Collection in another Collection, try the following with list and list2 as our two Collections −list.removeAll(list2);Example Live Demoimport java.util.ArrayList; import java.util.List; public class Demo { public static void main(String args[]) throws Exception { Listlist = new ArrayList(); list.add(100); list.add(200); list.add(200); list.add(200); list.add(300); ... Read More
Let us first create a table with one column as datetime and another wherein the days are stored:mysql> create table DemoTable ( ShippingDate datetime, CountOfDate int ); Query OK, 0 rows affected (0.52 sec)Following is the query to insert some records in the table using insert command:mysql> insert into DemoTable values('2018-01-31', 6); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('2016-12-01', 15); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable values('2016-12-01', 10); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('2016-12-01', 5); Query OK, 1 row affected (0.17 sec) ... Read More
The LinkedTransferQueue Class in Java has a transfer queue that has unbounded functionality and is based on linked nodes. It uses FIFO for ordering elements. This class implements the Collection interface as well as the AbstractQueue class. It is a part of the Java Collection Framework.A program that demonstrates this is given as follows −Example Live Demoimport java.util.concurrent.LinkedTransferQueue; public class Demo { public static void main(String[] args) throws InterruptedException { LinkedTransferQueue ltQueue = new LinkedTransferQueue(); ltQueue.add("Amy"); ltQueue.add("John"); ltQueue.add("May"); ltQueue.add("Harry"); ltQueue.add("Anne"); ... Read More
A duplicate buffer of a buffer can be created using the method duplicate() in the class java.nio.CharBuffer. This duplicate buffer is identical to the original buffer. The method duplicate() returns the duplicate buffer that was created.A program that demonstrates this is given as follows −Example Live Demoimport java.nio.*; import java.util.*; public class Demo { public static void main(String[] args) { int n = 5; try { CharBuffer buffer1 = CharBuffer.allocate(5); buffer1.put('A'); buffer1.put('P'); buffer1.put('P'); buffer1.put('L'); ... Read More
In the Bucket Sorting technique, the data items are distributed of a set of buckets. Each bucket can hold similar type of data. After distributing, each bucket is sorted using another sorting algorithm. After that all elements are gathered into the main list to get the sorted form.The complexity of Bucket Sort TechniqueTime Complexity: O(n + k) for best case and average case and O(n2 ) for worst case.Space Complexity: O(nk) for worst caseInput − A list of unsorted data: 0.25 0.36 0.58 0.41 0.29 0.22 0.45 0.79 0.01 0.69 Output − Array after Sorting: 0.01 0.22 0.25 0.29 0.36 ... Read More
Before getting into an example, we should know what sqlite database in android is. SQLite is an open source SQL database that stores data to a text file on a device. Android comes in with built-in SQLite database implementation. SQLite supports all the relational database features. In order to access this database, you don't need to establish any kind of connections for it like JDBC, ODBC etc.This example demonstrate about How to use sqlite_version () in Android sqliteStep 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create ... Read More
This example demonstrate about How to get programmatically android build id.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml. In the above code, we have taken text view to show device id.Step 3 − Add the following code to src/MainActivity.javapackage com.example.myapplication; import android.Manifest; import android.app.ProgressDialog; import android.content.pm.PackageManager; import android.os.Build; import android.os.Bundle; import android.support.annotation.RequiresApi; import android.support.v4.app.ActivityCompat; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.webkit.CookieManager; import android.webkit.WebChromeClient; import android.webkit.WebSettings; import android.webkit.WebView; import android.webkit.WebViewClient; import ... Read More
The tag is used to specify the encoding type used by forms that post data back to the Web application.AttributeThe tag has the following attributes −AttributeDescriptionRequiredDefaultkeyName of character encoding you want to apply when decoding request parameters.YesNoneYou use the tag when you want to specify the character encoding for decoding data posted from forms. This tag must be used with character encodings that are different from ISO-8859-1. The tag is required since most browsers do not include a Content-Type header in their requests.The purpose of the tag is to specify the content type of the request. ... Read More
To iterate through Decade Tuple, work it like any other collection in Java i.e. using a for loop, iterate and display the elements. Let us first see what we need to work with JavaTuples. To work with Decade class in JavaTuples, you need to import the following packageimport org.javatuples.Decade;Note: Download JavaTuples Jar library to run JavaTuples program. If you are using Eclipse IDE, then Right Click Project -> Properties -> Java Build Path -> Add External Jars and upload the downloaded JavaTuples jar file. Refer the below guide for all the steps to run JavaTuples:Steps: How to run JavaTuples program ... Read More