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🎨 Abstract Factory Design Pattern in Java In today's post of my design pattern series, let’s explore the Abstract Factory Pattern! 🚀 🛠️ What is it? The Abstract Factory Pattern allows us to create families of related objects without specifying their concrete classes. It’s especially useful when you want a consistent theme or behavior across related components. 💡 Key Highlights 🌐 Provides an interface for creating families of related or dependent objects. ⚙️ Ensures consistency across a set of objects (e.g., light and dark themes). 🔄 Decouples client code from specific implementations. 🎨 Use Case in UI Development Imagine building a GUI with light and dark themes. Using the Abstract Factory Pattern, you can switch between themes seamlessly without modifying client code. It handles the creation of theme-specific Button and TextField components efficiently. 🔑 Benefits 🔥 Decoupling: Clients don’t need to know the concrete classes being used. 🌍 Scalability: Adding new themes or families of objects is simple and non-disruptive. ⚙️ Flexibility: Perfect for cross-platform or plugin-based architectures. 📖 For the detailed implementation and example code, check out my GitHub repository: https://lnkd.in/d4ggjsAR 💬 Let’s keep the discussion going! Share your thoughts, or let me know how you’ve used the Abstract Factory Pattern in your projects. Don't forget to check-out README for clear understanding. Stay tuned for the next design pattern post! 🚀 #Java #DesignPatterns #SoftwareDevelopment #JavaDevelopers #AbstractFactory #CodingLife #ProgrammingTips #SoftwareEngineering #TechInsights #CleanCode #LearnToCode #ProgrammingCommunity

𝐂𝐨𝐧𝐬𝐭𝐫𝐮𝐜𝐭𝐨𝐫𝐬 𝐢𝐧 𝐉𝐚𝐯𝐚 Automatic initialisation of objects during the creation is done by a special method of the class known as constructor. 𝐅𝐞𝐚𝐭𝐮𝐫𝐞𝐬 𝐨𝐟 𝐂𝐨𝐧𝐬𝐭𝐫𝐮𝐜𝐭𝐨𝐫: • A constructor has the same name as the class. • A constructor is called automatically upon the creation of an object. • A constructor does not have a return type (Actually a constructor returns an instance of a class). • In case you provide your own constructor then you will not get any constructor from the compiler out of the box. • Creating an object with the help of a new keyword is known as instantiation. 𝐓𝐲𝐩𝐞 𝐜𝐨𝐧𝐬𝐭𝐫𝐮𝐜𝐭𝐨𝐫𝐬: 𝟏. 𝐃𝐞𝐟𝐚𝐮𝐥𝐭 𝐂𝐨𝐧𝐬𝐭𝐫𝐮𝐜𝐭𝐨𝐫𝐬: If constructors are not defined by the programmer then java compiler automatically provides a default constructor. A default constructor automatically initialized all the variables i.e. inter variables to zero, floating point to zero in decimal and string to null. Null represents no value at all. 𝟐. 𝐍𝐨 𝐀𝐫𝐠𝐮𝐦𝐞𝐧𝐭 𝐂𝐨𝐧𝐬𝐭𝐫𝐮𝐜𝐭𝐨𝐫: A constructor with no argument is known as no argument constructor. The signature is the same as the default constructor, however the body can have any code unlike the default constructor where the body is empty. 𝟑. 𝐏𝐚𝐫𝐚𝐦𝐞𝐭𝐞𝐫𝐢𝐳𝐞𝐝 𝐂𝐨𝐧𝐬𝐭𝐫𝐮𝐜𝐭𝐨𝐫: Constructors with arguments are known as parameterised constructors. 𝟒. 𝐂𝐨𝐧𝐬𝐭𝐫𝐮𝐜𝐭𝐨𝐫 𝐂𝐡𝐚𝐢𝐧𝐢𝐧𝐠: Calling a constructor from another constructor of the same class is known as constructor chaining. The real purpose of constructor chaining is that you can pass parameters through a bunch of different constructors but have initialisation done at a single place. This allows you to maintain initialisation at a single place. If we do not use constructor chaining and two different constructors have different signatures then we would need to perform the initialisation at multiple places in a class and if there is any change then you would have to change initialisation at all the places instead of just one. this() should always be the first in the constructor otherwise you will get errors as below. 𝐞𝐫𝐫𝐨𝐫: 𝐜𝐨𝐧𝐬𝐭𝐫𝐮𝐜𝐭𝐨𝐫 𝐜𝐚𝐥𝐥 𝐦𝐮𝐬𝐭 𝐛𝐞 𝐭𝐡𝐞 𝐟𝐢𝐫𝐬𝐭 𝐬𝐭𝐚𝐭𝐞𝐦𝐞𝐧𝐭 𝐢𝐧 𝐚 𝐜𝐨𝐧𝐬𝐭𝐫𝐮𝐜𝐭𝐨𝐫 #JavaExperts #JavaTraining #JavaInstructors #JavaSkills #JavaProgramming #JavaDevelopment #JavaClasses #JavaEducation #JavaCertification #JavaTutorials

𝐈𝐝𝐞𝐧𝐭𝐢𝐟𝐲𝐢𝐧𝐠 𝐂𝐨𝐝𝐞 𝐒𝐦𝐞𝐥𝐥 𝐚𝐧𝐝 𝐀𝐩𝐩𝐥𝐲𝐢𝐧𝐠 𝐭𝐡𝐞 𝐀𝐧𝐭 𝐏𝐚𝐭𝐭𝐞𝐫𝐧 𝐢𝐧 𝐉𝐚𝐯𝐚 𝐂𝐨𝐝𝐞 𝐒𝐦𝐞𝐥𝐥 When developing in Java, it's important to be aware of code patterns that may indicate problems or necessary improvements. "Code Smell" is a term used to describe these patterns. A common example of "Code Smell" is the God Object, where a class has too many responsibilities and becomes difficult to maintain. 𝐀𝐧𝐭𝐢𝐩𝐚𝐭𝐭𝐞𝐫𝐧 To address this type of problem, we can turn to design patterns like the Antipattern. A well-known example of an "Antipattern" is the Singleton, which can lead to issues with concurrency and testability. 𝐒𝐢𝐦𝐩𝐥𝐢𝐟𝐢𝐞𝐝 𝐒𝐨𝐥𝐮𝐭𝐢𝐨𝐧 To resolve the "God Object," we can apply the Strategy design pattern. This involves extracting parts of the large, complex class into smaller, more specialized classes, each with its own responsibility. To avoid problems with the "Singleton," you can use the Dependency Injection (DI) pattern. Instead of creating an instance directly in the class, the dependency is passed through a constructor or method, making it easier to swap out and test different implementations. Thus, when identifying a "Code Smell" such as a "God Object," consider applying the Strategy pattern. And when avoiding an "Antipattern" like the "Singleton," adopt the Dependency Injection (DI) pattern. These practices can help improve the quality and maintainability of your Java code. #JavaCodeSmell #AntiPattern #RefactoringSimplified

🎉 Factory Design Pattern in Java Today, we’re continuing our series on design patterns with the Factory Pattern! 🚀 This pattern is widely used to create objects without specifying the exact class of object that will be created. It provides a way to encapsulate the object creation process, making the code more modular and decoupled. 🛠️ What is the Factory Pattern? The Factory Pattern defines an interface or abstract class for creating objects. The concrete factory classes implement this interface and return an object of a particular type. 💡 Why Factory Pattern? 🔥 Promotes code modularity and separation of concerns 🌍 Eliminates dependencies on specific classes, enabling flexible code changes 💾 Helps manage complex object creation logic and reduces tight coupling 🔑 Key Use Cases ✅ When you need to create objects in a way that’s independent of the client code that uses them ✅ When you have multiple classes with a shared interface ✅ When dealing with large codebases where changing object creation logic in one place benefits the entire system 📖 For more details, check out the complete code examples on GitHub: https://lnkd.in/dBdRfnqr 💬 This is the third post in our design patterns series. Do not forget to check out README for a clear understanding. Let me know your thoughts or share how you use the Factory Pattern in your projects! Let’s discuss! 🚀 #Java #DesignPatterns #SoftwareDevelopment #JavaDevelopers #CodingLife #ProgrammingTips #FactoryPattern #SoftwareEngineering #TechInsights #CodeSharing #CleanCode #OOP #LearnToCode #ProgrammingCommunity #TechLearning

🚀 Prototype Design Pattern in Java We continue our series on design patterns, and today, we’re diving into the Prototype Design Pattern! 🧩 The Prototype Pattern allows for creating new objects by copying an existing one, making it a great solution when creating new instances is complex or costly. Instead of building from scratch, we clone objects for efficiency! Here’s a quick look at the three key approaches to implementing the Prototype pattern: 1️⃣ Shallow Cloning Shallow cloning copies the object, but nested objects are still shared by reference. It’s faster but may lead to unintended side effects due to shared references. Use it when objects are simple or immutable. 2️⃣ Deep Cloning Deep cloning creates a fully independent copy, ensuring all referenced objects are also cloned. It’s perfect when we need complete isolation between the original and the clone, but it's slower and more memory-intensive. 3️⃣ Registry-Based Prototype This approach keeps prototypes in a registry and clones them when needed. It’s useful for managing complex object creation, centralizing it in a registry for easier access and reuse. 💡 Which approach to choose? Shallow Cloning: When performance matters and the object graph is simple. Deep Cloning: When full independence is crucial between the original and the clone. Registry-Based Prototype: When you need to manage multiple prototypes dynamically. Check out the detailed code and examples of these approaches here: GitHub Link - Prototype Design Pattern 🔗 https://lnkd.in/dnkbKdJg Don't forget to checkout README for clear understanding! 🌟 Stay tuned for more posts in this series on Design Patterns! Would love to hear your thoughts or experiences with the Prototype pattern. Let’s discuss in the comments! 👇 #Java #DesignPatterns #SoftwareDevelopment #CodingLife #JavaDevelopers #ProgrammingTips #ObjectOrientedProgramming #SoftwareEngineering #CleanCode #TechInsights #LearnToCode #ProgrammingCommunity

𝗦𝗶𝗻𝗴𝗹𝗲𝘁𝗼𝗻 & 𝗜𝗺𝗺𝘂𝘁𝗮𝗯𝗹𝗲 𝗖𝗹𝗮𝘀𝘀𝗲𝘀: 𝗠𝗮𝘀𝘁𝗲𝗿𝗶𝗻𝗴 𝗝𝗮𝘃𝗮 𝗗𝗲𝘀𝗶𝗴𝗻 𝗣𝗮𝘁𝘁𝗲𝗿𝗻𝘀! Understanding Singleton and Immutable Classes is essential for writing efficient, maintainable code. Let's dive in! 🔑 𝗦𝗶𝗻𝗴𝗹𝗲𝘁𝗼𝗻 𝗖𝗹𝗮𝘀𝘀 Purpose: Ensures only one instance of a class is created. 𝗨𝘀𝗲 𝗖𝗮𝘀𝗲𝘀: • Database connections • Configuration settings ✨ 𝗜𝗺𝗽𝗹𝗲𝗺𝗲𝗻𝘁𝗮𝘁𝗶𝗼𝗻 𝗠𝗲𝘁𝗵𝗼𝗱𝘀: 1️⃣ Eager Initialization: Object is created upfront. 2️⃣ Lazy Initialization: Object is created only when needed (not thread-safe!). 3️⃣ Synchronized Method: Ensures thread safety, but less efficient. 4️⃣ Double-Check Locking: Efficient, but requires precision to avoid memory issues. 5️⃣ Bill Pugh Solution: A sleek approach using a static inner class. 6️⃣ Enum Singleton: The most concise way to implement Singleton. 💡 𝗜𝗺𝗺𝘂𝘁𝗮𝗯𝗹𝗲 𝗖𝗹𝗮𝘀𝘀 Purpose: Objects that cannot change after creation. 𝗦𝘁𝗲𝗽𝘀 𝘁𝗼 𝗜𝗺𝗽𝗹𝗲𝗺𝗲𝗻𝘁: ✅ Declare class as final. ✅ Make fields private and final. ✅ Use a constructor for field initialization. ✅ Provide only getter methods. ✅ Return copies of mutable fields in getters. ✨ 𝗕𝗼𝗻𝘂𝘀 𝗧𝗶𝗽: Java's Wrapper Classes (like Integer, Double) are perfect examples of immutability. They also support autoboxing/unboxing for seamless primitive-to-object conversion. 💡 𝗙𝘂𝗻 𝗙𝗮𝗰𝘁: Did you know that Java's String class is immutable because it helps optimize memory usage? 🧠 In the Java String Pool, all identical strings share the same memory location, reducing redundancy and improving performance. Imagine how chaotic memory would be without it!  💬 Which pattern do you use most frequently, and why? Let’s discuss in the comments! 👇 💡 𝗜𝗺𝗮𝗴𝗲 𝗖𝗿𝗲𝗱𝗶𝘁: 𝗖𝗿𝗲𝗮𝘁𝗲𝗱 𝘄𝗶𝘁𝗵 𝘁𝗵𝗲 𝗵𝗲𝗹𝗽 𝗼𝗳 𝗢𝗽𝗲𝗻𝗔𝗜'𝘀 𝗖𝗵𝗮𝘁𝗚𝗣𝗧. #Java #Programming #DesignPatterns #SoftwareDevelopment #TechTips

Iterator Design Pattern: https://lnkd.in/gH2bZMZd In this video, we explore the Iterator Design Pattern in Java, a fundamental design pattern that allows sequential access to elements of a collection without exposing its underlying structure. Using practical examples with both an array of books and a HashMap of magazines, we demonstrate how to implement and use iterators effectively. #IteratorDesignPattern #JavaIterator #DesignPatternsJava #IteratorPatternExample #JavaCollections #JavaHashMapIterator #JavaArrayIterator #IteratorVsForLoop #SoftwareDesignPatterns #CodingTutorial #JavaTutorial #LetsCodeTogether #IteratorPatternInJava #JavaBestPractices #JavaDevelopment #JavaProgramming #DesignPatternsInJava

🚀🚀🚀Interface: ➡️Blueprint of a class ➡️It has static constants and abstract methods. ➡️Used to achieve abstraction. ➡️There can be only abstract method in the java interface,not method body. ➡️Used to achieve abstraction and multiple inheritance in Java. 🔴Syntax: interface <interface_name>{ // declare constant fields // declare methods that abstract // by default. } 🔗Relationship between classes and interfaces ➡class ---> extends ---> class ➡interface ---> implements ---> interface ➡interface ---> extends ---> interface 📢IMP Points: ⚡We can’t create an instance (interface can’t be instantiated) of the interface but we can make the reference of it that refers to the Object of its implementing class. ⚡A class can implement more than one interface. ⚡An interface can extend to another interface or interface. ⚡A class that implements the interface must implement all the methods in the interfac ⚡All the methods are public and abstract. And all the fields are public, static, and final. ⚡It is used to achieve loose coupling ⚡Inside the Interface, constructors are not allowed. ⚡Inside the interface main method is not allowed. ⚡Inside the interface, static, final, and private methods declaration are not possible. #interface #java #springboot #hibernate

Deserialization: A Hidden Threat to Singletons Singletons ensure that a class has only one instance, providing a global point of access. However, deserialization can put this design pattern in jeopardy by creating a new instance of the Singleton class, thereby breaking the singleton contract. Here's how to safeguard your Singleton during deserialization: Java Example: import java.io.Serializable; public class Singleton implements Serializable { private static final Singleton instance = new Singleton(); private Singleton() {} public static Singleton getInstance() { return instance; } // This method ensures the singleton is not broken during deserialization protected Object readResolve() { return instance; } } C# Example: using System; using System.Runtime.Serialization; [Serializable] public class Singleton : ISerializable { private static readonly Lazy<Singleton> instance = new Lazy<Singleton>(() => new Singleton()); private Singleton() {} public static Singleton Instance => instance.Value; // This method ensures the singleton is not broken during deserialization protected Singleton(SerializationInfo info, StreamingContext context) { // No additional data needed, but prevents another instance } public void GetObjectData(SerializationInfo info, StreamingContext context) { // Implement ISerializable interface } [OnDeserialized] private void OnDeserialized(StreamingContext context) { // Ensure that the deserialized instance is the singleton instance if (instance.IsValueCreated) throw new InvalidOperationException("Deserialization is not allowed for a singleton instance."); } } In both examples, special mechanisms are employed to prevent the creation of new instances during deserialization. In Java, the readResolve() method returns the existing instance, while in C#, overriding OnDeserialized ensures the singleton's integrity. Even seemingly minor oversights in design can lead to significant consequences. It’s crucial to consider these edge cases to maintain the robustness of your architecture. #SoftwareEngineering #SingletonPattern #Deserialization #DesignPatterns #Csharp #Java #CodingBestPractices

Day 12 of Solving LeetCode 75 [ q- 14 ] Maximum Average Subarray I You are given an integer array nums consisting of n elements, and an integer k. Find a contiguous subarray whose length is equal to k that has the maximum average value and return this value. Any answer with a calculation error less than 10^-5 will be accepted. Example 1: Input: nums = [1,12,-5,-6,50,3], k = 4 Output: 12.75000 Explanation: Maximum average is (12 - 5 - 6 + 50) / 4 = 51 / 4 = 12.75 Example 2: Input: nums = [5], k = 1 Output: 5.00000 Constraints: n == nums.length 1 <= k <= n <= 105 -104 <= nums[i] <= 104 In a java class 1. Create a method which accepts an array of numbers and a integer variable k. 2. Initialize a long variable to store the sum of k integers. 3. Use a for loop to find the sum of first k elements. 4. Initialize a variable to store the maximum sum. 5. Iterate through the array starting from index k. 6. Update the sum by adding the current element and subtracting the element at position (i - k). 7. Update the maximum sum. 8. Calculate and return the maximum average by dividing the maximum sum by k. Time Complexity: The code iterates through the array nums only once, both iterations have a time complexity of O(n), where n is the length of the array nums, therefore, the overall time complexity is O(n). Space Complexity: The code uses a constant amount of extra space regardless of the input size, therefore, the space complexity is O(1), constant space complexity. #java #leetcode