Programming in Java

Unit 1: Introduction to Java

From "Hello World" to understanding how 3 billion devices run Java — master Java basics, JVM architecture, and start building real programs.

⏱️ 4 hrs theory + 3 hrs lab | 💰 Earning Potential: ₹5,000–₹20,000/month | 📝 30 MCQs (Bloom's Mapped)

💼 Jobs: Java Intern (₹15K–25K/month) | Jr Java Dev (₹4–6 LPA) | Interview: TCS NQT / Infosys SP

Section A

Opening Hook — Java Runs Your India

☕ 3 Billion Devices. One Language. YOUR Career.

Open the Ola app to book a cab — Java. Transfer ₹500 via BHIM UPI — Java. Book a Tatkal ticket on IRCTC at 10:00 AM while 25 million others do the same — Java. Check your PhonePe balance — Java. Browse Flipkart's Big Billion Days sale — Java backend.

Java doesn't just run on your phone. It powers 3 billion+ devices worldwide — from Android smartphones to ATM machines, from satellite systems to stock trading platforms. Every major Indian IT company — TCS, Infosys, Wipro, HCL — has more Java developers than any other language.

Could YOU have built any of this? After this unit, you'll understand how Java works from source code to execution. You'll write your first programs, understand why Java is called "Write Once, Run Anywhere," and know exactly what happens when you type javac and java. This is where your Java career begins.

🇮🇳 Ola🇮🇳 BHIM/UPI🇮🇳 IRCTC🇮🇳 PhonePe🇮🇳 Flipkart🇮🇳 Infosys

Java was originally called "Oak" — named after an oak tree outside James Gosling's office at Sun Microsystems. When they discovered that name was already trademarked, the team renamed it "Java" after Indonesian Java coffee that they loved drinking. Today, the ☕ coffee cup is Java's official logo. The language runs on 3+ billion devices — more than any other programming language in history.

Section B

Learning Outcomes — Bloom's Taxonomy Mapped

Bloom's Level	Learning Outcome
🔵 Remember	1. List Java's key features and trace its history from Oak (1991) to Java 21 (2023)
🔵 Remember	2. Define JDK, JRE, and JVM and state their individual roles in Java execution
🔵 Understand	3. Explain Java's platform independence through the bytecode-JVM mechanism
🔵 Understand	4. Describe the complete compilation and execution pipeline: .java → javac → .class → JVM
🟢 Apply	5. Write, compile, and execute a Java HelloWorld program using command-line tools
🟢 Apply	6. Use command-line arguments to pass data into a Java program and access via args[]
🟢 Analyze	7. Compare Java with C, C++, and Python across paradigm, memory management, speed, and platform dependence
🟢 Analyze	8. Differentiate between JDK, JRE, and JVM using real-world Indian analogies
🟠 Evaluate	9. Assess why Java is preferred for enterprise applications in Indian IT companies (TCS, Infosys, Wipro)
🟠 Evaluate	10. Justify Java's "Write Once, Run Anywhere" claim with technical evidence from the bytecode-JIT pipeline
🟠 Create	11. Design a multi-feature Java console program that processes command-line arguments
🟠 Create	12. Build a Student ID Card Printer that accepts name, roll number, and branch via cmd-line args and prints formatted output