How to boost performance with Lazy Loading and JdbcTemplate

🚀 Day 6 of 30 Days of Data Structures Challenge Topics Covered Today: 🔹 Java Collection Framework (JCF) – LinkedList 🔹 Explored in-built LinkedList methods like add(), remove(), get(), addFirst(), addLast() and more. 🔹 Implemented Merge Sort on a LinkedList from Scratch. 📂 Code: https://lnkd.in/gk5-kdKv https://lnkd.in/gfdmpVWf #Java #DataStructures #LinkedList #MergeSort #JCF

How to Create a Composite Primary Key in JPA Sometimes a single column isn’t enough to uniquely identify a record - that’s when we use a composite primary key. JPA gives two clean ways to implement it: @IdClass and @EmbeddedId. > The @Embeddable class holds the combined key fields. > The entity uses @EmbeddedId to mark the composite key. When to use: When two or more fields together uniquely identify a row When modeling many-to-many join tables When avoiding auto-generated IDs Composite keys keep your data consistent and enforce real-world uniqueness directly in the database. #SpringBoot #JPA #Hibernate #Java

𝗛𝗼𝘄 𝗝𝗮𝘃𝗮 𝗥𝗲𝗮𝗹𝗹𝘆 𝗪𝗼𝗿𝗸𝘀: 𝗙𝗿𝗼𝗺 𝗖𝗼𝗱𝗲 𝘁𝗼 𝗘𝘅𝗲𝗰𝘂𝘁𝗶𝗼𝗻 𝗠𝗮𝗴𝗶𝗰 Ever wondered what happens behind the scenes when you hit Run on a Java program? Here’s what makes the Java engine truly timeless 👇 🔹 Compilation Phase Your .java files are converted by javac into platform-independent bytecode (.class) — not bound to any OS or CPU. 🔹 Class Loading & Verification The ClassLoader dynamically loads the bytecode into the JVM, validating access rights, structure, and memory safety before execution. 🔹 Execution Phase The Interpreter runs bytecode line-by-line, while the JIT Compiler spots frequently executed code paths (“hot methods”) and converts them into native machine code for high performance. 🔹 Memory & Runtime Management The Garbage Collector reclaims unused memory, while runtime profiling and JIT inlining continuously fine-tune performance. 💡 Java’s real magic? It blends portability, safety, and speed through a layered runtime — making it one of the most resilient platforms in software history. #Java #JVM #SpringBoot #Java25 #SoftwareEngineering #BackendDevelopment ##ModernJava #CloudNative #SpringBoot #SpringSecurity #GraphQL #Java25 #Microservices #CloudNative #PlatformEngineering #TechLeadership #FullStackJava #Performance #APIManagement #Java17 #SpringFramework #Serverless #Docker #CI_CD #C2C #H1B #W2 #Jobs #ModernJava #ReactiveProgramming

📌 LeetCode Day 57 — #107. Binary Tree Level Order Traversal II Problem Description: Given the root of a binary tree, return the bottom-up level order traversal of its nodes' values. That means you need to traverse the tree level by level from left to right, but from the bottom level up to the root. Approach: Use a Queue (BFS): Perform a standard level order traversal using a queue. Store Each Level: For each level, store the node values in a temporary list. Insert at Beginning: Instead of appending levels at the end, insert each level at index 0 to reverse the order. Return Result: The final list represents the bottom-up traversal. Complexity Analysis: Time Complexity: O(n) — every node is visited once. Space Complexity: O(n) — queue and result storage for all nodes. Hashtags: #BinaryTree #BFS #LogicBuilding #LeetCode100Days #Day57 #Java #ProblemSolving

Day 10 of the Java Developer Challenge was dedicated to building the first RESTful API Endpoint for reading data. With a solid foundation in the three-tier architecture and MVC pattern, the focus shifted to practical application. By creating a simple GET mapping to retrieve data, a significant milestone was achieved in the transition from theoretical Spring concepts to real-world development. Key Concepts Applied: - **@RestController**: Utilized to define a class that manages HTTP requests and directly returns data (commonly in JSON or XML format) without involving a view name. - **@RequestMapping / @GetMapping**: Specified the URI path and designated the method to handle HTTP GET requests for resource retrieval. - **API Design**: Ensured adherence to REST principles by emphasizing the resource (e.g., /api/users) and selecting the appropriate HTTP verb. - **Separation of Concerns**: Maintained a clear distinction in responsibilities by having the Controller solely manage request handling, delegating business logic (data fetching) to the Service Layer, and returning the output. This practical implementation signifies the crucial transition from theory to application, marking a pivotal moment in the Java Developer Challenge journey! 🚀 #JavaDeveloper #21DayChallenge #Day10 #RESTAPI #SpringBoot #GetMapping #Controller #BackendDevelopment

🚀 Understanding @Async in Spring Boot — Simplify Asynchronous Processing! In real-world applications, performance matters — especially when handling time-consuming operations like sending emails, processing large files, or calling external APIs. That’s where Spring’s @Async annotation shines ✨ 👉 What is @Async? @Async allows you to run a method in a separate thread, freeing up the main thread to continue processing other tasks. Simply put, it helps improve application responsiveness and scalability. @Service public class EmailService { @Async public void sendEmail(String recipient, String message) { // Simulate delay try { Thread.sleep(3000); } catch (InterruptedException e) { } System.out.println("Email sent to: " + recipient); } } @SpringBootApplication @EnableAsync public class MyApplication { public static void main(String[] args) { SpringApplication.run(MyApplication.class, args); } } Now, when you call sendEmail(), it will execute asynchronously without blocking the caller thread. 💡 Pro tip: • Use @Async carefully for methods that are independent and don’t need to return immediate results. • You can even return a CompletableFuture<T> to handle async results gracefully. ⸻ ⚙️ Use case examples: • Sending notifications or emails • Background report generation • Data synchronization tasks #SpringBoot #Java #Async #Multithreading #BackendDevelopment #PerformanceOptimization

Why You Should Add a Name to Unique Constraints in JPA When defining unique constraints in JPA, it’s good practice to give them a name - and here’s why 👇 1. Easier debugging: When a constraint is violated, the database throws an error with the constraint name. A clear name like uk_user_email helps you identify the issue instantly. 2. Database portability: Different databases generate random names for unnamed constraints. By naming them yourself, you ensure consistency across environments. 3. Better maintainability: Named constraints make schema updates or migrations easier to manage. 📍 Always use descriptive, lowercase names like uk_table_column for clarity and convention. #SpringBoot #JPA #Hibernate #Java

Where does your technical debt really hide? Cyclomatic complexity, churn, coupling — Richard Gross demonstrates how to measure and visualize deep problems in large codebases objectively. Read now on JAVAPRO: https://lnkd.in/eENXrUwD #Java #DomainDrivenDesign #LegacyCode

#100DaysOfCode – Day 73 String Manipulation Problem: Valid Anagram (LeetCode #242) Task: Given two strings s and t, return true if t is an anagram of s, otherwise false. Example: Input: s = "anagram", t = "nagaram" → Output: true Input: s = "rat", t = "car" → Output: false My Approach:- Method 1 – Sorting Converted both strings into character arrays. Sorted them and compared if equal, they’re anagrams! Time Complexity: O(n log n) Method 2 – Frequency Count (Optimized) Counted occurrences of each character in s and t. If every count matches, it’s a valid anagram. Time Complexity: O(n) | Space: O(1) String problems may look simple, but optimizing from sorting to counting makes a huge difference. Small logic shifts often lead to big performance gains! #100DaysOfCode #Java #ProblemSolving #LeetCode #CodingJourney #takeUforward #DataStructures #Algorithms #StringManipulation #GeeksForGeeks #CodeNewbie

💻 Day 03/10 of Linked List Series: Inserting a Node at the Beginning of a Linked List Let’s understand how we can add a new node at the start of a linked list 👇 ⚙️ Algorithm: Insert at Beginning Create a new node with the given data (for example, 'A'). Set the next pointer of this new node to point to the current head of the list. Now, make this new node the new head of the linked list. 💡 In simple terms: you’re placing a new link before the first link in the chain. 🧩 Example Explanation: Initial list: B → C → D We want to insert 'A' at the beginning. Steps: Create a new node 'A'. Point 'A' → 'B'. Return node 'A'. ✅ Final list becomes: A → B → C → D ✨ This operation is one of the most common and easiest insert operations in linked lists — it just needs a few pointer adjustments! 📚 Stay tuned for the next part in this #LinkedListSeries! Follow my Brand 👉 #CodeWithLakkojuEswaraSai #CodeWithLakkojuEswaraSai_LinkedList #DSA #Java #10000coders