Java Programming Course by Mosh

Introduction

• Instructor: Mosh
• Course Objectives:
  • Learn basics of Java programming
  • Install necessary tools
  • Build Java applications
  • Write good, professional code
  • Gain a solid foundation in Java
  • Prepare for advanced Java features
• Target Audience: Beginners

About the Instructor

• Name: Mosh
• Experience: 20 years as a software engineer
• Students taught: Over 3 million
• Runs online coding school: codewithmosh.com

Course Content Overview

Installing Tools

1. Java Development Kit (JDK)
   • Software to build Java applications
   • Download from Oracle.com
   • Available for Linux, Mac OS, Windows
2. Code Editors
   • Popular editors: NetBeans, Eclipse, IntelliJ
   • Recommended: IntelliJ (Community Edition is free)

Java Basics

• Anatomy of a Java Program
  • Functions (block of code performing a task)
  • Return Types: void (no return), other types (number, datetime, etc.)
  • Function Naming: descriptive names (e.g., sendEmail)
  • Parameters in parentheses
  • Code inside curly braces
  • Every program should have a main function
  • main function is the entry point
  • Functions belong to a class
  • Class Declaration: public class ClassName {}
  • Access Modifiers: public, private, etc.
  • Naming Conventions: Pascal for classes, camel for methods

Writing and Executing Java Programs

1. Creating a New Project in IntelliJ
2. Using Templates (Command Line Application)
3. Naming Projects and Packages
4. Running the Program

Java Execution Process

1. Compilation to Bytecode
2. Execution with Java Runtime Environment (JRE) and Java Virtual Machine (JVM)

Data Types and Variables

• Primitive Types: byte, short, int, long, float, double, char, boolean
• Reference Types: objects and classes
• Declaration, Initialization, and Memory Allocation
• Naming Conventions: CamelCase, descriptive names

Working with Strings

• Creation and Initialization
• Useful Methods: concatenate, length, indexOf, replace, toLowerCase, toUpperCase, trim
• Escape Sequences: \, \n, \t, \"

Arrays

• Declaration and Initialization: int[] numbers = new int[5]; or {1, 2, 3}
• Multi-dimensional Arrays
• Arrays Utility Class: Arrays.toString(), Arrays.deepToString()

Constants

• Declaring with final

Arithmetic Operations

• Operators: +, -, *, /, %
• Increment and Decrement: i++, i--
• Augmented Assignment: +=, -=, *=, /=

Casting and Type Conversion

• Implicit vs Explicit Casting
• Converting Strings to Numbers: using wrapper classes Integer.parseInt(), Double.parseDouble(), etc.

Math Class

• Methods: round, ceil, floor, max, min, random

Formatting Numbers

• NumberFormat Class: currency, percentage
• Method Chaining

Reading Input

• Scanner Class: scanner.nextInt(), scanner.nextLine()
• Handling White Spaces: trim()

Control Flow

• Comparison Operators: ==, !=, >, <, >=, <=
• Logical Operators: &&, ||, !
• If Statements: if...else if...else
• Simplifying If Statements: ternary operator ? :
• Switch Statements: Simplifies multiple conditions

Looping

• For Loop: [initialization]; [condition]; [increment/decrement]
• While Loop: Repeats while condition is true
• Do-While Loop: Executes at least once, checks condition after loop
• For-Each Loop: Iterates over arrays/collections
• Break and Continue: break exits loop, continue skips to loop start

Error Handling

• Importance of Adding Error Handling and Data Validation
• Adding Infinite Loops to Ensure Valid Input

Clean Coding

• Importance of Writing Clean Code for Maintainability
• Techniques for Improving and Refactoring Code