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The findFirst() method of the LongStream class in Java returns an OptionalLong describing the first element of this stream, or an empty OptionalLong if the stream is empty.The syntax is as follows.OptionalLong findFirst()Here, OptionalLong is a container object which may or may not contain a long value. For OptionalLong, import the following package.import java.util.OptionalLong;To use the LongStream class in Java, import the following package.import java.util.stream.LongStream;Create a LongStream and add elements.LongStream longStream = LongStream.of(25000L, 35000L, 40000L, 50000L, 60000L);Now, get the first element from the stream.OptionalLong res = longStream.findFirst();The following is an example to implement LongStream findFirst() method in Java.Example Live Demoimport java.util.OptionalLong; ... Read More
To add elements to the ArrayBlockingQueue class, use the add() method.The syntax is as followsboolean add(E ele)Here, ele is the element to be added to the queue. To work with ArrayBlockingQueue class, you need to import the following packageimport java.util.concurrent.ArrayBlockingQueue;The following is an example to add elements in Java ArrayBlockingQueue classExample Live Demoimport java.util.concurrent.ArrayBlockingQueue; public class Demo { public static void main(String[] args) { ArrayBlockingQueue q = new ArrayBlockingQueue(7); q.add(100); q.add(250); q.add(300); q.add(450); q.add(550); q.add(600); q.add(700); System.out.println("ArrayBlockingQueue = " + q); } }OutputArrayBlockingQueue = [100, 250, 300, 450, 550, 600, 700]
The syntax is as follows to skip the duplicate value and select only one from the duplicated values −select min(yourColumnName1), yourColumnName2 from yourTableName group by yourColumnName2;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table doNotSelectDuplicateValuesDemo -> ( -> User_Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> User_Name varchar(20) -> ); Query OK, 0 rows affected (0.78 sec)Now you can insert some records in the table using insert command. The query is as follows −mysql> insert into doNotSelectDuplicateValuesDemo(User_Name) values('John'); Query OK, 1 row affected ... Read More
In this section we will see how to perform sorting algorithm in C++. A sorted array is an array in which each of the elements are sorted in some order such as numerical, alphabetical etc. There are many algorithms to sort a numerical array such as bubble sort, insertion sort, selection sort, merge sort, quick sort, heap sort etc. More details about sorting the array using selection sort are given below.The selection sort is a sorting method that yields a sorted array. It does so by repeatedly finding the smallest element in the array and interchanging it with the element ... Read More
How to add checkbox list in alert dialog?This example demonstrates How to add checkbox list in the alert dialogStep 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.Step 3 − Add the following code to src/MainActivity.javapackage com.example.myapplication; import android.annotation.TargetApi; import android.content.DialogInterface; import android.os.Build; import android.os.Bundle; import android.support.v7.app.AlertDialog; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Switch; import android.widget.TextView; import android.widget.Toast; public class MainActivity extends AppCompatActivity { ... Read More
To create a calculator with Java Swings, try the following code −Exampleimport java.awt.Color; import java.awt.Container; import java.awt.FlowLayout; import javax.swing.JFrame; import javax.swing.JLabel; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JTextField; public class SwingDemo extends JFrame implements ActionListener { JButton one, two, three, four, five, six, seven, eight, nine, num0, add, sub, div, mult, equalto, exit, point, reset; JTextField textField; String s = "", ope = ""; int flag = 0; double total1; double input1, input2; void total(double input1, double inout2, String ope) { String total; if (ope.equalsIgnoreCase("+")) ... Read More
You can use CASE statement for this and set conditions to get result in the temporary column.Let us first create a table −mysql> create table DemoTable ( EmployeeId int NOT NULL AUTO_INCREMENT PRIMARY KEY, EmployeeName varchar(20), EmployeeSalary int, EmployeeExperience int ); Query OK, 0 rows affected (0.64 sec)Following is the query to insert some records in the table using insert command −mysql> insert into DemoTable(EmployeeName, EmployeeSalary, EmployeeExperience) values('Larry', 4500, 5); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable(EmployeeName, EmployeeSalary, EmployeeExperience) values('Mike', 130000, 8); Query OK, 1 row affected (0.21 sec) mysql> ... Read More
You can use $set operator for this Let us first create a collection with documents −> db.updateRecordDemo.insertOne({"StudentName":"Larry"}); { "acknowledged" : true, "insertedId" : ObjectId("5cbd6f95de8cc557214c0e0a") } > db.updateRecordDemo.insertOne({"StudentName":"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5cbd6f9cde8cc557214c0e0b") } > db.updateRecordDemo.insertOne({"StudentName":"Mike"}); { "acknowledged" : true, "insertedId" : ObjectId("5cbd6f9dde8cc557214c0e0c") }Display all documents from a collection with the help of find() method −> db.updateRecordDemo.find().pretty();This will produce the following output −{ "_id" : ObjectId("5cbd6f95de8cc557214c0e0a"), "StudentName" : "Larry" } { "_id" : ObjectId("5cbd6f9cde8cc557214c0e0b"), "StudentName" : "David" } { "_id" : ObjectId("5cbd6f9dde8cc557214c0e0c"), "StudentName" : "Mike" }Following is the query to update record in ... Read More
To exactly count all rows, you need to use the aggregate function COUNT(*). The syntax is as follows −select count(*) as anyAliasName from yourTableName;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table CountAllRowsDemo -> ( -> Id int, -> Name varchar(10), -> Age int -> ); Query OK, 0 rows affected (1.49 sec)Now you can insert some records in the table using insert command. The query is as follows −mysql> insert into CountAllRowsDemo values(1, 'John', 23); Query OK, 1 row affected (0.15 ... Read More
An immutable copy of a duration where some days are added to it can be obtained using the plusDays() method in the Duration class in Java. This method requires a single parameter i.e. the number of days to be added and it returns the duration with the added days.A program that demonstrates this is given as follows −Example Live Demoimport java.time.Duration; public class Demo { public static void main(String[] args) { Duration d = Duration.ofDays(5); System.out.println("The duration is: " + d); ... Read More