Explore

Getting Started with Java

Summary - Getting Started with Java

Why Choose Java?

What is Programming?

Programming involves writing precise instructions for a computer to perform tasks.

Various languages like Java and Python serve as mediums to instruct computers, each with unique features.

Understanding Java

Java is a high-level, class-based, object-oriented language.

It's designed to be readable and resembles human language more than machine language.

High-Level vs. Low-Level Languages

High-Level Languages: Human-readable, requiring a compiler to translate into machine code (e.g., Java, Python).

Low-Level Languages: Closer to machine language, faster for execution but harder to understand (e.g., Assembly, Machine Code).

Why Java Stands Out

Versatility: Used in various applications like Android apps, web apps, and enterprise software.

Cross-Platform Compatibility: "Write Once, Run Anywhere" philosophy.

Market Presence: Large ecosystem supported by millions of developers.

Key Advantages of Java

Platform Independence: Runs on any device.

Ease of Learning: Simple syntax.

Performance, Scalability, and Security: Suitable for applications of any size.

Regular Updates: Keeps Java relevant and adaptable.

⁠

Your First Java Program

The Three-Step Process

Creating Your Java File: Write your Java code in a file named FirstProgram.java.

Compiling Your Java File: Use the Java compiler to transform the .java file into a .class file.

Running Your Compiled File: Execute the .class file to see the output.

⁠

Common Mistakes by Beginners

Encountering Syntax Errors

Missing Closing Parentheses: Ensure all parentheses are closed properly.

Unclosed String Literal: Close all strings with a double quote.

Case Sensitivity: Correctly use uppercase and lowercase letters as required.

Utilizing Comments

Single-line Comments: Use // to comment out a single line.

Multi-line Comments: Use /* to start and */ to end a block of comments.

⁠

Understanding JDK, JRE, and JVM

The Role of Compilers

General Compilers: Convert programs into machine-readable format.

Java Compiler: Compiles Java code into bytecode, an intermediate format.

JDK vs. JRE

Java Development Kit (JDK): For building and compiling Java applications, includes JRE.

Java Runtime Environment (JRE): For running compiled Java applications, includes JVM.

Java Virtual Machine (JVM)

Converts bytecode into machine code, handling code loading, verification, execution, and memory management.

Just-In-Time (JIT) Compiler

Optimizes code execution by pre-compiling frequently executed parts into machine code, enhancing performance.

⁠

How is Java Platform Independent?

Bytecode: The Key to Platform Independence

Source Code to Bytecode: Java code is compiled into bytecode, an intermediate format.

Universal Bytecode: Can be executed on any platform using the JVM, making Java programs portable across different systems.

This concept of Java Fundamentals are very usefull in understanding core java. For more detailed information, refer to the Notion link:

Getting Started with Java⁠

⁠

Want to print your doc?
This is not the way.

Try clicking the ⋯ next to your doc name or using a keyboard shortcut (

CtrlP

) instead.