Java Basics

What you will learn

1. 1.1Getting Started

   What Java is, what the JDK, JRE and JVM are, how to install Java, how to set up one IDE (VS Code, IntelliJ IDEA or Eclipse), and how to write and run your first program.

   1. What is Java?Free10 min
   2. JDK, JRE and JVMFree10 min
   3. Install Java (JDK) on your computerFree20 min
   4. Set up VS Code for JavaFree20 min
   5. Set up IntelliJ IDEA for JavaFree20 min
   6. Set up Eclipse for JavaFree20 min
   7. Your first Java programFree20 min

2. 1.2Variables & Data Types

   Store values in variables, meet Java's data types (int, long, double, float, char, boolean and String), convert between types, make constants with final, and fix common beginner mistakes.

   1. What is a variable?18 min
   2. Data types in Java18 min
   3. Whole numbers: int and long18 min
   4. Decimal numbers: double and float18 min
   5. char and boolean14 min
   6. Text with String18 min
   7. Type conversion and casting24 min
   8. Constants with final14 min
   9. Common mistakes and practice25 min

3. 1.3Operators

   Do calculations with arithmetic operators, change variables with =, +=, ++ and --, compare values, join conditions with &&, || and !, pick one of two values with ?:, and learn the order Java runs operators in.

   1. Arithmetic operators22 min
   2. Assignment and compound assignment18 min
   3. Increment and decrement: ++ and --20 min
   4. Comparison operators20 min
   5. Logical operators: &&, || and !22 min
   6. The ternary operator ?:14 min
   7. Operator precedence and parentheses20 min
   8. Common mistakes and practice28 min

4. 1.4Input & Output

   Print output with println, print and printf, read keyboard input with Scanner, choose between next() and nextLine(), fix common input errors, and build small console programs.

   1. Printing with println and print16 min
   2. Formatted output with printf20 min
   3. Reading input with Scanner18 min
   4. Reading numbers, words and characters18 min
   5. next() vs nextLine() and the Enter key20 min
   6. Common input errors16 min
   7. Mini programs and practice28 min

5. 1.5Conditional Statements

   Make decisions in Java with if, if-else and else-if ladders, join checks with && and ||, nest one if inside another, pick a case with switch and arrow switch expressions, and fix common condition bugs.

   1. The if statement12 min
   2. if-else: choose one of two paths14 min
   3. The else-if ladder18 min
   4. Combine conditions with && and ||16 min
   5. Nested if15 min
   6. The switch statement20 min
   7. switch with arrows (->)16 min
   8. Common mistakes and practice28 min

6. 1.6Loops

   Repeat code with loops: write for, while and do-while loops, trace a loop to find totals and counts, stop or skip rounds with break and continue, print patterns with nested loops, and fix common loop mistakes.

   1. Why loops?14 min
   2. The for loop20 min
   3. Tracing a loop: totals and counts22 min
   4. while and do-while loops24 min
   5. break and continue20 min
   6. Nested loops and star patterns25 min
   7. Common mistakes and practice30 min

7. 1.7Methods

   Split a program into small methods: define and call a method, send values in with parameters, get a result back with return, understand local variables and pass-by-value, overload a method, start with recursion, and fix common method mistakes.

   1. Why use methods?12 min
   2. Define and call a method18 min
   3. Parameters and arguments20 min
   4. Return a value from a method22 min
   5. Local variables and scope18 min
   6. Pass-by-value: a method gets a copy15 min
   7. Method overloading18 min
   8. Recursion: a method that calls itself20 min
   9. Common mistakes and practice30 min

8. 1.8Arrays

   Store many values in one variable with arrays: create an array, read and change elements by index, loop through it with for and for-each, find totals, largest values and matches, pass arrays to methods, use 2D arrays and the Arrays class, and fix common array mistakes.

   1. What is an array?14 min
   2. Creating an array18 min
   3. Reading and changing array elements18 min
   4. Looping through an array20 min
   5. The for-each loop18 min
   6. Sum, average, largest and search25 min
   7. Arrays and methods25 min
   8. 2D arrays: rows and columns25 min
   9. The Arrays class: print, sort and compare18 min
   10. Common mistakes and practice30 min

9. 1.9Strings

   Work with text in Java: read characters by index, search with indexOf, cut text with substring, change case and trim, compare Strings with equals(), loop through characters, split and parse text, build text with StringBuilder, and fix common String mistakes.

   1. String recap: characters and index positions15 min
   2. Search in a String: indexOf, contains, startsWith15 min
   3. Cut out part of a String with substring()20 min
   4. Change case, trim and replace (Strings never change)20 min
   5. Compare Strings: equals() and compareTo()20 min
   6. Loop through the characters of a String20 min
   7. Split, join and turn text into numbers20 min
   8. Build and change text with StringBuilder20 min
   9. Common mistakes and practice30 min

10. 1.10Exception Basics

    Handle runtime errors so a program does not crash: read a stack trace, recognise common exceptions, use try, catch and finally, throw an exception and declare it with throws, and keep asking until the user types valid input. Custom exception classes come later in the OOP section.

    1. What is an exception?15 min
    2. Common exceptions you will see18 min
    3. Handle an exception with try and catch18 min
    4. Multiple catch blocks18 min
    5. The finally block15 min
    6. throw and throws22 min
    7. Keep asking until the input is valid20 min
    8. Common mistakes and practice30 min

11. 1.11Packages, Imports & Access Control

    Organize Java classes into packages: see why packages exist, create your own package and run it, use classes from other packages with import, control who can use a class, field or method with public, private and default access, and build a small app from two packages.

    1. Why do we need packages?15 min
    2. Create your own package20 min
    3. Use classes from other packages with import25 min
    4. Access modifiers: public, private and default25 min
    5. Build an app with two packages25 min
    6. Common mistakes and practice30 min

12. 1.12Java Basics Mini Projects

    Put Java Basics together in five small console projects: a calculator, a number guessing game, a student marks report, a text analyzer and an ATM simulator. Each project is built step by step, pushed to GitHub and submitted as a link.

    1. Build a simple calculator40 min
    2. Build a number guessing game40 min
    3. Build a student marks report50 min
    4. Build a text analyzer50 min
    5. Build an ATM simulator60 min