Programming Articles - Page 3309 of 3366

An object is created from a class. In Java, the new keyword is used to create new objects. There are three steps when creating an object from a class − Declaration − A variable declaration with a variable name with an object type. Instantiation − The 'new' keyword is used to create the object. Initialization − The 'new' keyword is followed by a call to a constructor. This call initializes the new object. Following is an example of creating an object − Example Live Demo public class Puppy { public Puppy(String name) { ... Read More

A constructor is a special method in Java that is used to initialize objects. It gets called when an instance of a class is created. The constructor has the same name as the class and does not have a return type. The question is whether a constructor can be declared or made final in Java? The answer is no. Let's understand why. Why can't we declare a Java Constructor "final"? In Java, the final keyword is used to restrict modification of the members of a class (methods and variables). For example, a final method of a class cannot be overridden ... Read More

No, constructors are not inherited in Java.

Creating an empty file is a common task in programming when we are initializing log files, setting up placeholders or working with automation scripts. Python provides several easy and flexible methods to create empty files. In this article, we'll go through different ways to create an empty file in Python. Using open() with Write Mode 'w' The open() function is the most straightforward way to create an empty file. When we use the write mode 'w', then it creates a new file if it doesn't exist. Example Following is an example, which shows how to create an empty file using ... Read More

No, the constructor does not return any value. While declaring a constructor you will not have anything like a return type. In general, the Constructor is implicitly called at the time of instantiation. And it is not a method, its sole purpose is to initialize the instance variables.Read more about constructors: Java Constructors Example public class Sample{ public Sample(){ System.out.println("This is a constructor"); } public static void main(String args[]){ ... Read More

In some scenarios, it is important to determine the MIME type of a file to verify its content type, especially when working with file uploads or handling media files. Python provides modules such as mimetypes and magic to determine the MIME type of a file. In this article, we’ll explore different methods to find a file's MIME type using Python. Using mimetypes.guess_type() The mimetypes module in Python provides the guess_type() function, which is used to guess the MIME type and to encode of a file based on its filename or URL. Example In this example, we are using the mimetypes.guess_type() ... Read More

No, you cannot have both this() and super() in a single constructor.

Constructors are similar to methods but, They do not have any return type. The name of the constructor is same as the name of the class. Every class has a constructor. If we do not explicitly write a constructor for a class, the Java compiler builds a default constructor for that class. Each time a new object is created, at least one constructor will be invoked. A class can have more than one constructor. this() and super() are used to call constructors explicitly. Where, using this() you can call the current class’s constructor and using super() you can ... Read More

In a few scenarios, we need to extract the extension of a file to perform specific operations based on its type, such as validating image formats or filtering document files. Python provides different ways to achieve this using the os and pathlib modules. In this article, we'll explore how to get a file’s extension with different approaches.  Using os.path.splitext() The OS file path manipulation is made simple with the help of the Python os.path module. It provides methods to perform operations to receive data from file paths, opening, saving, and updating. The os.path.splitext() method of the os module in Python ... Read More

Java 8 introduces a new concept of default method implementation in interfaces. This capability is added for backward compatibility so that old interfaces can be used to leverage the lambda expression capability of Java 8. For example, ‘List’ or ‘Collection’ interfaces do not have ‘foreach’ method declaration. Thus, adding such method will simply break the collection framework implementations. Java 8 introduces default method so that List/Collection interface can have a default implementation of foreach method, and the class implementing these interfaces need not implement the same. Syntax public interface vehicle { default void print() { ... Read More