Java StringBuilder vs StringBuffer: Performance and Thread Safety

#Day13 – Advanced Strings & Mutable vs Immutable 🤯 Today was all about Advanced String concepts and understanding Mutable vs Immutable in Java. ✔ Difference between immutable and mutable strings ✔ How concat() creates a new object in Heap ✔ How reference update changes output ✔ Difference between String, StringBuffer, and StringBuilder ✔ Initial capacity (16) and dynamic capacity formula (n * 2 + 2) ✔ Methods like length(), charAt(), toCharArray() ✔ Split vs StringTokenizer (why split is recommended) TAP Academy Harshit T #Java #Strings #StringBuilder #StringBuffer #CoreJava #ProgrammingJourney #Consistency

A stream in java is a sequence of objects, its just a way to get data out of a collection. Collection interface in java has the stream method so all collections support stream. Arrays dont have a stream method we can make a stream out of an array by using Arrays util class's stream static method. Stream is used to process data from a collection in a declarative way much like we do chaining of array methods in JS/TS. We can have finite or infinite streams. #Java #Backend #SoftwareEngineering

Leetcode Problem | | Check If a String Contains All Binary Codes (1461) 🚀 Problem: Given a binary string s and integer k, check if all possible binary codes of length k exist in the string. Example: s = "00110", k = 2 Expected Output = true In substring and sliding window problems, boundary conditions matter more than logic sometimes. Consistent debugging > frustration. #DSA #Java #LeetCode #ProblemSolving #LearningInPublic

Day 10- What I Learned In a Day(JAVA) In the real world, input is not inbuilt-the user has to provide it. Today, I learned how to take user input in Java and understood how the Scanner class works. I learned: ✔ Why Java does not automatically take input ✔ How System.in reads from the keyboard ✔ How nextLine() reads full user input ✔ How to create a Scanner object import java.util.Scanner; class ClassName { public static void main(String[] args) { Scanner sc = new Scanner(System.in); // input here sc.close(); } } and also using the new tool(VSCODE) practiced 👇 #Java #LearningJourney #CodingDaily #JavaDeveloper

Leetcode Problem || Complement of Base 10 Integer(1009) 🚀 The Bitwise Complement problem using Java. 🔹 Idea: The complement of a number means flipping all bits in its binary representation (0 → 1 and 1 → 0). Instead of manually converting the number to binary, I used a bit manipulation trick: 1️⃣ Find the highest set bit using Integer.highestOneBit(n) 2️⃣ Create a mask with all bits set to 1 up to that position 3️⃣ Use XOR (^) with the mask to flip the bits #LeetCode #Java #BitManipulation #CodingPractice #ProblemSolving #SoftwareDevelopment

Day 14- What I Learned in a Day(JAVA) Concatenation Operator :("+") • Used to combine two or more strings • Commonly used to join text with variables • Helps in displaying meaningful output messages Increment Operator: • Used to increase a variable value by one • Can be used in pre-increment(++varname) and post-increment(varname ++) form Decrement Operator: • Used to decrease a variable value by one • Can be used in pre-decrement(--varname) and post-decrement(varname--) form. 🔹 I practiced small programs to understand how these operators behave during execution and how output changes based on their usage. Practiced 👇 #Java #JavaProgramming #OperatorsInJava #CodingPractice #LearningJourney #ProgrammingLife #TechSkills #FutureDeveloper 🚀

🚀 Day 76 of #100DaysOfCode Today I solved a string manipulation problem: Clear Digits 🧠 Problem: Given a string, whenever a digit appears, remove the previous character. Digits act like a backspace operation. 💡 Key Insight: Instead of modifying the string directly (since Strings are immutable in Java), I used a StringBuilder, which works like a stack: If character → append (push) If digit → delete last character (pop) 📌 What I Learned: StringBuilder is powerful for string modifications Always handle edge cases (like digit at the start) Many string problems are actually stack problems in disguise ⏱ Complexity: Time: O(n) Space: O(n) #Java #DSA #LeetCode #CodingJourney #100DaysOfCode #ProblemSolving

• String & String Constant Pool • Immutability & Memory Management • String Comparison Techniques • Concatenation Methods & Performance Tests • substring(), split(), indexOf() • String vs StringBuffer vs StringBuilder • Immutable Class Design • toString() Method • StringTokenizer (Legacy vs Modern Approach) Understanding how Strings work internally is crucial for writing efficient, optimized, and interview-ready Java code. Strong fundamentals. Clean code. Better performance. #Java #CoreJava #JavaDeveloper #DSA #StringConcepts #Coding #LearningJourney #CodesInTransit #InterviewPreparation #MondayMotivation #RevisitingTheTopics

✨ Day 16 of 90 – Pattern Mastery Journey 🧠 Pattern: Number Triangle Pattern 💡 Approach: ✔ Used nested loops ✔ Outer loop controls the number of rows ✔ Inner loop prints numbers from 1 to current row number ✔ Each row increases the sequence of numbers 🚀 This pattern helped me better understand loop control and how patterns grow step-by-step using nested loops in Java. #PatternMasteryJourney #Java #CodingJourney #ProblemSolving

Day 45 — LeetCode Progress (Java) Problem: Intersection of Two Arrays Required: Given two integer arrays nums1 and nums2, return an array containing their unique intersection elements. Idea: Use a HashSet to efficiently track elements from the first array and check their presence in the second array. Approach: Create a HashSet to store all elements from nums1. Traverse nums1 and insert each element into the set. Initialize a list to store the intersection result. Iterate through nums2: If an element exists in the set: Add it to the result list. Remove it from the set to avoid duplicates. Convert the result list into an array and return it. Time Complexity: O(n + m) n = length of nums1 m = length of nums2 Space Complexity: O(n) #LeetCode #DSA #Java #HashSet #Arrays #CodingJourney #100DaysOfCode