Templates in C++ vs Generics in Java

Arjun Thakur
Updated on 30-Jul-2019 22:30:26

2K+ Views

Templates are the foundation of generic programming, which involves writing code in a way that is independent of any particular type.A template is a blueprint or formula for creating a generic class or a function. The library containers like iterators and algorithms are examples of generic programming and have been developed using template concept.There is a single definition of each container, such as vector, but we can define many different kinds of vectors for example, vector or vector .Example Code#include #include using namespace std; template inline T const& Max (T const& a, T const& b) { ... Read More

Create Vertical Progress Bar Occupying Entire Frame in Java

Anvi Jain
Updated on 30-Jul-2019 22:30:26

300 Views

For this, create a vertical progress bar −JProgressBar progressBar = new JProgressBar(JProgressBar.VERTICAL); progressBar.setEnabled(true);Also, set the bounds −progressBar.setBounds(70, 50, 120, 30);The following is an example to create vertical progress bar occupying the entire frame −Examplepackage my; import java.awt.BorderLayout; import java.awt.Color; import javax.swing.JFrame; import javax.swing.JProgressBar; public class SwingDemo {    public static void main(String[] args) {       JFrame frame = new JFrame();       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);       JProgressBar progressBar = new JProgressBar(JProgressBar.VERTICAL);       progressBar.setEnabled(true);       progressBar.setBounds(70, 50, 120, 30);       progressBar.setBackground(Color.orange);       progressBar.setForeground(Color.white);       progressBar.setStringPainted(true);       ... Read More

Merge Two Array Fields in MongoDB

Anvi Jain
Updated on 30-Jul-2019 22:30:26

726 Views

To merge, use $setUnion operator. Let us first create a collection with documents −> db.mergeTwoArrayFieldDemo.insertOne({"NaturalNumbers":[1,2,3,8,10,20,30],"WholeNumbers":[0,1,2,63,78,20,45]}); {    "acknowledged" : true,    "insertedId" : ObjectId("5cd68e4057806ebf1256f11d") }Following is the query to display all documents from a collection with the help of find() method −> db.mergeTwoArrayFieldDemo.find().pretty();This will produce the following output −{    "_id" : ObjectId("5cd68e4057806ebf1256f11d"),    "NaturalNumbers" : [       1,       2,       3,       8,       10,       20,       30    ],    "WholeNumbers" : [       0,       1,       2,       63,       78,       20,       45    ] }Following is the query to merge two array field in MongoDB.> db.mergeTwoArrayFieldDemo.aggregate([    { "$project": {       "MergedArray": { "$setUnion": [ "$NaturalNumbers", "$WholeNumbers" ] }    }} ]);This will produce the following output −{ "_id" : ObjectId("5cd68e4057806ebf1256f11d"), "MergedArray" : [ 0, 1, 2, 3, 8, 10, 20, 30, 45, 63, 78 ] }

Use an Array of Pointers for Jagged Arrays in C++

Smita Kapse
Updated on 30-Jul-2019 22:30:26

660 Views

Let us consider the following example, which uses an array of 3 integers −In CExample Live Demo#include const int MAX = 3; int main () {    int var[] = {10, 100, 200};    int i;    for (i = 0; i < MAX; i++) {       printf("Value of var[%d] = %d", i, var[i] );    }    return 0; }OutputValue of var[0] = 10 Value of var[1] = 100 Value of var[2] = 200In C++Example Live Demo#include using namespace std; const int MAX = 3; int main () {    int var[] = {10, 100, 200};    int i;    for (i = 0; i < MAX; i++) {       cout

Different Types of Nested Classes in Java

raja
Updated on 30-Jul-2019 22:30:26

1K+ Views

In Java, it is possible to define a class inside another class, such classes are called Nested classes. We can use the access modifiers like private, public, protected or default for inner classes and default or public access modifiers for outer class.There are two types of nested classes are defined in Java.Static Nested ClassNon-Static Nested ClassStatic Nested ClassWe Can define an inner class as static, so such type of classes is called a static nested class.The nested class is defined with the static keyword, so this type of nested classes doesn’t share any relationship with the instance of an outer class.A static ... Read More

Adding Double Value to a String in Java

Venkata Sai
Updated on 30-Jul-2019 22:30:26

2K+ Views

The “+” operator with a String acts as a concatenation operator.Whenever you add a String value to a double using the “+” operator, both values are concatenated resulting a String object.In-fact adding a double value to String is the easiest way to convert a double value to Strings.Exampleimport java.util.Scanner;    public class StringsExample {       public static void main(String args[]){          Scanner sc = new Scanner(System.in);          System.out.println("Enter a double value: ");          double d = sc.nextDouble();          System.out.println("Enter a String value: ");       ... Read More

HTML DOM Input Hidden Type Property

Sharon Christine
Updated on 30-Jul-2019 22:30:26

141 Views

The HTML DOM input hidden type property returns the value of type attribute of input field.SyntaxFollowing is the syntax −object.typeExampleLet us see an example of HTML DOM input hidden type property − Live Demo    body{       text-align:center;       background-color:#F19A3E;       color:#fff;    }    .btn{       background-color:#3C787E;       border:none;       height:2rem;       border-radius:50px;       width:60%;       margin:1rem auto;       display:block;       color:#fff;       outline:none;    }    .show{       color:#fff;   ... Read More

A C Programming Language Puzzle

Arnab Chakraborty
Updated on 30-Jul-2019 22:30:26

528 Views

Here we will see one C programming language puzzle question. Suppose we have two numbers 48 and 96. We have to add the first number after the second one. So final result will be like 9648. But we cannot use any logical, arithmetic, string related operations, also cannot use any pre-defined functions. So how can we do that?This is easy. We can do by using Token Pasting operator(##) in C. The Token Pasting operator is a preprocessor operator. It sends commands to compiler to add or concatenate two tokens into one string. We use this operator at the macro definition.Example Live ... Read More

Convert File into a Stream in Java

Nancy Den
Updated on 30-Jul-2019 22:30:26

775 Views

Let’s say we have a file “input.txt” here in the directory E:/ with the following content:Open a file with Bufferedreader. We have taken the above file here which is located at E: directory;BufferedReader buffReader = Files.newBufferedReader(Paths.get("E:\input.txt"), StandardCharsets.UTF_8);Now get the stream of lines from the above file and display:buffReader.lines().forEach(System.out::println);The following is an example to convert File into a Stream in Java:Exampleimport java.io.BufferedReader; import java.nio.charset.StandardCharsets; import java.nio.file.Files; import java.nio.file.Paths; public class Demo {    public static void main(String[] argv) throws Exception {       BufferedReader buffReader = Files.newBufferedReader(Paths.get("E:\input.txt"), StandardCharsets.UTF_8);       System.out.println("Stream of lines...");       buffReader.lines().forEach(System.out::println);    } ... Read More

Set Action Command to JButton in Java

Krantik Chavan
Updated on 30-Jul-2019 22:30:26

4K+ Views

With set action command, here we are displaying a message in the console on the click of a button.Set the button first:JButton btn = new JButton("Demo Button");Now, set Action Listener to fire when the button is clicked:ActionListener actionListener = new ActionListener() {    public void actionPerformed(ActionEvent event) {       String str = event.getActionCommand();       System.out.println("Clicked = " + str);    } };The following is an example to set action command to JButton:Exampleimport java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JOptionPane; public class SwingDemo {    public static void main(final String args[]) {       JButton btn ... Read More

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