Must Know Object Oriented Programming in Java

Define objects as concrete instances of a class. Describe a class as a general category with attributes, behaviors, and a bank account example; introduce instance variables.

Explore core Java topics in section 2, including visibility modifiers, constructors, parameters and arguments, assignment operators, relational operators and conditional statements, assignment versus equality, exceptions, and types of comments.

Explore the assignment operator in Java by assigning a string color with quotes and printing it to verify initialization, noting right-to-left evaluation and type compatibility.

Demonstrate assignment statements by showing how to assign one variable's value to another, initializing balance in USD and cash deposit in USD, with the left-hand side receiving the value.

Explain that a multi line comment in Java uses /* and */ to comment multiple lines, with possible asterisks and content ignored by the compiler.

Explore how return types in Java determine what a method yields, using char and string examples, and how to fix mismatches with return statements and void.

Explore string concatenation in Java by combining a display text with an integer score to print messages like your score is 10, and distinguish concatenation from addition.

Know the basics of section 4: learn logical operators (and &&, or ||, not !), short circuit evaluation, fields and parameters, and variable types (local, static), symbolic constants for maintainability.

Demonstrates the Java logical and operator in if statements using x and y examples and prints results to the console.

explain the modulus operator in java, which returns the remainder of division, with examples like 100 mod 3, 10 mod 3, and 8 mod 3, plus shorthand modulo assignment.

Identify which data types are valid in a switch statement—integral types such as int, byte, short, long, and char—and learn why boolean and floating point values require an if statement.

Explore how Java switch statements test only equality via the implicit boolean condition and why relational checks are not allowed, with examples of errors and proper case syntax.

Explore external method calls in Java by referencing an object and using public getters to access private fields. Instantiate objects with new and use the dot operator to invoke methods.

In Java, test primitive value equality with the == operator, but test string value equality with the string equals method, because == checks identity while equals checks value.

Explore how Java uses collections and arrays to organize data, including fixed-size one-dimensional arrays of 100 players, printing array contents, and memory addresses.

Explore array lists in Java, compare them with arrays, and master key methods and the for each loop through real-life examples.