Programming Articles - Page 3288 of 3366

Yes, you can define an interface inside a class and it is known as a nested interface. You can’t access a nested interface directly; you need to access (implement) the nested interface using the inner class or by using the name of the class holding this nested interface.ExampleLive Demopublic class Sample {    interface myInterface {       void demo();    }    class Inner implements myInterface {       public void demo() {          System.out.println("Welcome to Tutorialspoint");       }    }    public static void main(String args[]) {       Inner obj ... Read More

Yes, you can define a class inside an interface. In general, if the methods of the interface use this class and if we are not using it anywhere else we will declare a class within an interface.Exampleinterface Library {    void issueBook(Book b);    void retrieveBook(Book b);    public class Book {       int bookId;       String bookName;       int issueDate;       int returnDate;    } } public class Sample implements Library {    public void issueBook(Book b) {       System.out.println("Book Issued");    }    public void retrieveBook(Book b) { ... Read More

An interface with no methods in it is referred to as a marker interface, also known as a tagging interface. There are two basic design purposes of marker interfaces. Creates a common parent  It is used to provide a common parent interface for a group of related interfaces. When an interface like "eventlistener" is extended by dozens of other interfaces in the Java API, we can use a marker interface to create a common parent among a group of interfaces. For example, when an interface extends EventListener, the JVM knows that this particular interface is going to be used in an ... Read More

A Dictionary in Python is a mutable, unordered collection of data in a key-value format. A dictionary can also contain another dictionary as a value, and this is known as a Nested Dictionary or a dictionary within a dictionary. In this article, we are going to explore all the different ways to use a dictionary within a dictionary in Python. Syntax to define a Dictionary within another Following is the syntax of creating a Dictionary within another Dictionary in Python - outer_dict = { 'key1': { 'inner_key1': ... Read More

When we are starting with Python, mostly created first program will be "Hello, World", which prints the statement "Hello, World" as the output. Before we begin with the first program, we need to install Python in our system from the official website. Choose a Code Editor After installing Python, we need to select the text editor based on our requirements and usage. Following are the different editors available - IDLE: It comes pre-installed with Python VS Code: A popular and lightweight code editor PyCharm: This is useful ... Read More

A dictionary in Python is a collection of key-value pairs. In a few cases, we may have to remove a key and its associated value from a dictionary. Python provides multiple ways to do this safely and efficiently. Using pop() method The pop() method is used to remove the specified key and returns the corresponding value. If the key does not exist, then it raises a KeyError unless a default value is provided. Example Following is an example, which shows how to remove a key from the dictionary using the pop() method - my_dict = {'a': 1, 'b': 2, 'c': ... Read More

In Python, a Dictionary is one of the data structures that contains key-value pairs enclosed in curly braces '{}'. It is a Mutable and unordered data structure. Before proceeding with adding new keys to a dictionary, first let's create a dictionary with key and values. Following is the example of creating a dictionary with specified key and values - dict1 = {'key1': 'Tutorials', 'key2': 'Point', 'key3': 'Python'} print("Created Dictionary:", dict1) Following is the output of the above example - Created Dictionary: {'key1': 'Tutorials', 'key2': 'Point', 'key3': 'Python'} Adding new keys to a Dictionary Once a Dictionary is ... Read More

In Python, a Dictionary is a unordered and muttable data structure which stores data as a key-value pair. In some cases, we may need to merge two dictionaries into a single dictionary by using a single expression, in such scenarios python provides different methods. Using | Merge Operator The | merge operator in Python is used to merge multiple dictionaries into one with a single expression and returns the combined dictionary as a new dictionary. If both dictionaries have the same key, then the value from the dictionary on the right side of the operator will be replaced with the ... Read More

In Python, converting different data types into strings is a common requirement when we want to display or store information in text format. The built-in str() function is used for this conversion. This function accepts any Python object as a parameter and returns a string representation of it. The basic syntax of the str() function is as follows: str(object) Where object is any valid Python object, such as int, float, bool, list, etc. In this article, we will explore different data type conversions into a string in Python. Conversion of Integer to String An integer can be converted into ... Read More

Data conversion in Python refers to changing the data type of a value to another data type. Python supports two different types of data conversion, such as Implicit conversion and explicit conversion. Implicit Conversion is performed by the Python interpreter automatically. Explicit Conversion is manually done by the programmer using built-in functions in Python Implicit Conversion Python automatically converts one data type to another, and this type of conversion is called Implicit conversion. To avoid any data loss during runtime, the smaller data type is converted ... Read More