Programming Articles - Page 2574 of 3363

Declaring Multiple Classes in Java Program A single Java program may contain two or more classes, it is possible in two ways: Multiple non-nested classes Nested classes The Multiple non-nested Classes We can create as many classes as we want in a single Java program but writing many classes in a single file is not recommended as it makes code difficult to read rather we can create a single file for every class. When we compile a Java program with two or more classes (non-nested), the same number of .class ... Read More

Method overriding works because of the run-time method binding feature in Java. So, if we force the Java compiler to do static binding for a method then we can prevent that method from being overridden in a derived class. Preventing Method Overriding in Java We can prevent method overriding in Java in 3 ways: By declaring a method as "final" in the base class By declaring a method as "static" in the base class By declaring a method as "private" in the base class Final Methods cannot be Overridden ... Read More

Palindrome is a string that even when reversed will be the same as the original string. In simple words, the palindrome string will have odd length and the element in 0th index and the last index will be the same, element in 1st index will be the same as the second last element and so on. The palindrome contains alphanumeric elements; that means it contains the alphabet(a-z) and digits (0-9) as well. A palindrome string must look like − var str = "121Malayalam121"; Let’s understand with a suitable example. Let’s understand with a suitable example. Example 1 In the ... Read More

To append text to JTextArea, use the component’s append() method. Let’sa say the following is our text in the JTextArea -JTextArea textArea = new JTextArea("The text added here is just for demo. "+ "This demonstrates the usage of JTextArea in Java. ");Now, append text to the same textArea -textArea.append("In this example we have deleted some text from the beginning."+ "We have also appended some text.");The following is an example to append text to JTextArea -Examplepackage my; import java.awt.GridLayout; import javax.swing.*; public class SwingDemo {    SwingDemo() {       JFrame frame = new JFrame("Demo");       JTextArea textArea ... Read More

PHP5 added the object-oriented programming approach with the previous version, which is used for making code reusable in real time php application.Some of the concepts of object-oriented models are: class, object, encapsulation, polymorphism, abstract and final classes, and methods, interfaces and inheritance, etc...Here we discuss the basic differences between abstraction and encapsulation.Encapsulation:Encapsulation is an approach that joins data members(variables) and implementation details into a single unit called the class that implies class is formed with variables and methods present inside it.Encapsulation is a protection mechanism for data members present inside the class i.e data members are not accessible by end ... Read More

Flattening an arrayFlattening an array is nothing but merging a group of nested arrays present inside a provided array. Flattening of an array can be done in two ways. 1) concat.apply() In the following example there are some nested arrays containing elements 3, 4, 5 and 6. After flattening them using concat() method we get the output as 1, 2, 3, 4, 5, 6, 9. Example Live Demo var arrays = [1, 2, [3, 4, [5, 6]], 9]; var merged = [].concat.apply([], arrays); documemt.write(merged); Output1, 2, 3, 4, 5, 6, 92) array.flat()In ... Read More

The Java team and developer community suggest us to follow naming conventions. They are just conventions and are not mandatory but help in writing Java programs that are more understandable and easier to read. For example, class names should generally be nouns, and interface names should be adjectives. Additionally, capitalize the first letter of each separate word. The names used for classes, variables, and methods are called identifiers. Need to Follow Java Naming Conventions Following are the reasons to follow naming conventions: Multiple developers work on the same project simultaneously. Names that follow naming standards reduce ... Read More

The default and parameterized constructors are two types of Constructor in Java. The constructor is a special member of a Java class whose name is the same as the class name. It is used to assign values to a class variable at the time of object creation. In this article, we are going to discuss the difference between default and parameterized constructors. Default Constructor When we do not add a constructor to a Java class. The compiler adds a default constructor implicitly. It accepts 0 arguments. If we do not initialize the instance variables of a class, a default constructor will ... Read More

In Java, a class is a datatype which defines properties (variables) and behaviors (methods) of an object. Defining an object does not consume memory; only its object or instance does.Depending on the requirement, we will create various types of classes in Java. In this article, we are going to discuss them. Types of classes in Java The Java class is classified into different types based on its methods, as shown in the list given below: Concrete class Abstract class Final class POJO class Static class Inner Class Wrapper Class Singleton Class Concrete class Any normal class which does ... Read More

The java.lang.Object class is the root or superclass of the class hierarchy, it belongs to the java.lang package. All predefined classes and user-defined classes are direct or indirect subclasses of the Object class. Why is Object Class a Superclass? To understand why the Object class is the superclass of every class in Java, we need to understand why a superclass is needed in the first place: To share common properties. To accept and return any type of object. Sharing Common Properties using Object Class There are 11 common properties that every ... Read More