Sneha Tiwari’s Post

✨Everyone these days is busy doing Ctrl + C and Ctrl + V — copying code, copying answers, copying shortcuts. But I am trying something different. ->Comparing my yesterday with today and becoming a better version of myself. 🙃Week 1 of my DSA + Java fundamentals journey with Kunal Kushwaha playlist is completed, and honestly, this week was mind-opening. Here’s what I learned this week: •The actual internally working is : ".java file" → "javac compiler" → "bytecode (.class)" → "JVM" → machine code → output. •Some important components I learned: - JDK (Java Development Kit): Used to develop, compile, and run Java programs - JRE (Java Runtime Environment): Contains the libraries and environment required to run Java applications - JVM (Java Virtual Machine): Responsible for executing bytecode and converting it into machine-understandable instructions •One important realization: Java is platform independent because of bytecode, but JVM itself is platform dependent. •Inside JVM: - Class Loader loads the bytecode - Bytecode Verifier checks the code for security and correctness - Interpreter / JIT compiler converts bytecode into machine code and executes it. I also completed lectures on: - "if-else" - loops - "switch" statements These are the core building blocks of logic formation. •I learned the difference between: - Implicit / automatic type conversion → done automatically by Java when converting smaller data types to larger ones - Explicit type casting → manually converting larger data types to smaller one. -This concept is very important for writing optimized code. Functions:-One of the most important lectures this week. •I learned that when similar code needs to run multiple times, functions help in reusability and cleaner code structure. •This was one of the most interesting concept -Java is strictly pass by value. -For primitive data types like: int,char, Boolean etc are just pass by value. -For objects and strings, Java passes the value of the reference, not the object itself. -This difference was really important to understand. ••Arrays and ArrayList-this lecture honestly gave me one of the clearest explanations I have seen. •I finally understood: - why arrays are used - how "ArrayList" works - syntax and internal dynamic resizing Also, an important concept I learned: Many people say arrays in Java are always stored in continuous memory. But practically, array objects are stored on the heap, and heap memory is not guaranteed to be continuous in the Java Language Specification. So the memory allocation depends on: - JVM implementation - heap allocation - dynamic memory management •This week was not just about learning syntax, but about strengthening the basics. The goal is simple: improve from yesterday to today. #Java #DSA #KunalKushwaha #LearningInPublic #ProgrammingJourney #Consistency