Learn Java Programming Crash Course

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Declare and name Java variables in a statically typed language, using int or var, follow identifier rules, avoid keywords, and spot common errors during coding.

Learn a Java interactive number guessing game that computes a result by multiplying the chosen number by two and five, dividing by the original number, then subtracting seven.

Initialize the answer at the point of declaration by moving the calculation from line 31 to line 17. Ensure the value is printed only after assignment.

Learn Java naming conventions to improve code readability for maintainers, using camelCase for variables and methods and capitalized class names, guided by Google Java Style Guide.

Refactor Doctor.java in the Eliza project to conform with Java naming conventions, identifying eight deviations and practicing careful code reading to spot and fix errors.

Explore how to declare and name Java variables, follow Pascal and Camel case conventions, and ensure variables are initialized before use for accurate calculations.

Use the scanner class to read keyboard input via system.in, print with system.out, and leverage nextLine, parse to numbers, and string formatting for aligned output and currency symbols.

Learn how to read a full line of user input from the console with the Scanner nextLine method in Java, implement a seven-option coffee menu, and display the user's choice.

Learn to use Java printf for advanced string formatting, control field width with positive and negative values, and align text and numbers using %s and %d.

Discover Java data types, choose between integer and floating point types, and apply variables in numeric and Boolean expressions (including and/or), with an intro to classes and fields.

Explore the int and long types in Java by printing their minimum and maximum values, using Integer and Long wrappers, and learn when to use ints or longs.

Compare java's float and double floating point types, examine their min and max values and precision in bits, and learn why double is preferred over float for most use cases.

Compare float and double precision by declaring a float and a double with f literals, print with high precision, and observe rounding errors, setting the stage for BigDecimal.

BigDecimal stores values as integers and tracks decimal position to preserve precision, delivering higher accuracy than float or double. Use its methods for arithmetic, not the plus or minus operators.

Master BigDecimal in Java to achieve precise decimal calculations using immutable values and methods like add and multiply, avoiding floating point errors.

Explore how Java expressions evaluate to a single value with literals. Observe arithmetic and boolean expressions in code, and that left-hand side must be a variable.

Master boolean expressions in Java by testing equality with two equal signs and not equal, using greater than equals and less than equals, with booleans printing true or false.

Analyze how booleans drive control flow in Java by examining the play method, boolean expressions, and loop conditions, and see how the final score is printed.

Identify and count boolean expressions in the Hammer Bitcoin Java project, exploring conditions for market crashes, hackers, purchases, sales, maintenance, payroll, and gameplay logic.

Explore the fundamentals of classes and objects as the building blocks of Java's object-oriented programs, including the main method, instances, and the scanner for console input with nextLine and println.

This lesson introduces Java classes by building a Car class with accelerate and brake methods. It covers creating car instances with new and distinguishing between objects and their class types.

Learn how class constructors initialize objects in Java, including default and parameterized constructors, field initialization with name, and printing name and speed to distinguish instances.

Explore encapsulation in Java by contrasting public and private modifiers, showing how public methods like accelerate and brake are used outside the class, while the show speed method remains internal.

Learn how to alter program flow with loops and conditionals, test conditions, and use methods, then debug code step-by-step with the IntelliJ IDEA debugger.

Explore the for loop in Java using the Oracle official tutorial and Java API documentation. Compare for loops with infinite and while loops while consulting the Java language specification.

Master the IntelliJ debugger to set breakpoints, run in debug mode, and inspect variables in Java. Learn how to step over and into code to understand loops and program flow.

Master for loops in Java by incrementing and decrementing the index, changing step sizes, and testing with the debugger, including zero and hinting at nested for loops.

Explore nested for loops, printing grids of digits, and learn how to use breakpoints and the debugger to diagnose infinite loops and ensure correct loop conditions.

Learn to use the hammerbitcoin project to debug, set breakpoints, and inspect variable values, while exploring constructors, new object creation, static versus instance members, and OGH constants.

Master debugging in IntelliJ by setting breakpoints, stepping into methods, and using resume, drop frame, and console inputs to observe BitcoinMiner’s flow, printFinalScore, and potential crashes.

Explore how Eliza analyzes input with indexOf, uses for loops to process matches and reflections, and drives randomized responses through the program flow.

Explore how Java makes decisions with if-else, switch, and the ternary operator; understand when to use each construct and how they direct code blocks based on conditions.

Learn to implement java if statements by building a rock, paper, scissors game, mapping user input to final constants and using equals, with a random move and output.

Explore advanced if-else logic in java to determine rock, paper, scissors outcomes, detect draws, apply cyclical win rules, and learn a modulus-based approach.

Implement a play again loop in a Java rock, paper, scissors game using a do-while loop, leveraging a getYesNo method to prompt would you like to play again.

Learn how to replace if/else with a Java switch statement to drive a vending machine menu, using case blocks and break inside a do-while loop to manage six options.

Learn how to add a default case to a Java switch to handle unmatched options, prevent errors, and guide program flow with a final else style behavior.

Discover how to use the Java switch statement to share code across multiple cases by grouping case one and case two, reducing duplication and preparing for break and continue keywords.

Demonstrate how the break statement exits for and while loops in Java, using a simplified list-search example and debugging with breakpoints to stop after finding a match.

See how the continue keyword skips remaining loop code and returns to the start, unlike break, with a vending machine menu example that handles invalid options and dispensing coffee.

Learn how Java's ternary operator acts as a concise alternative to if else, illustrated with a day check that yields relax or work. See toLowerCase usage and simple, readable syntax.

Apply the ternary operator in a Java project by replacing an if-else that computes new hires in the Hammer Bitcoin Project, based on starvation status and available computers and cash.

Master flow control with if/else, switch, and the ternary operator to test boolean expressions, use constants, and select code blocks, while breaking and continuing loops and handling default cases.

Declare methods, understand parameters and arguments, use the return keyword for values, and refactor to reduce global variables and side effects, clarifying scope with local variables and class fields.

Explore how Java method calls transfer execution through the call stack, using a Car class with accelerate and brake, and practice stepping into and over methods to observe speed.

Explore how nested method calls use the stack to track return addresses, and observe stepping through accelerate and showspeed with a debugger, inspecting frames and console output.

Download and add the JLine and Jansi libraries from the Maven Repository. Create a libs folder in IntelliJ, copy the JARs, and attach them as project dependencies.

Update your car game to version two by replacing main.java with a new version, using constants for controls and the JLine library to read input without pressing enter.

Learn how access modifiers control visibility in Java by making private methods accessible via public or protected ones, and using public getters like getSpeed to expose private fields.

Fix crash logic across all directions in a car game, reduce duplicated code by extracting common crash handling into a method, and plan proper arguments and testing.

Refactor the Java car game by extracting duplicate movement code into a drive method that takes speed and car position; consider scope, road constants, and a forthcoming understeer bug.

Explore how Java passes arguments by value and use of a global variable to update carPosition inside a static method, while noting global variables are generally bad practice.

Learn to refactor the car drive method by parameterizing position delta to left, straight, or right, fix line 117, and eliminate duplicate code in the straight and right cases.

Refactor a car game by adding a direction parameter to the drive method and using direction-based calls. Use constants for left, straight, and right to boost readability and consider enums.

Explore variable scope and class fields in the BitcoinMiner Java program, showing how public versus private access affects scope, and how side effects impact maintainable code.

learn to eliminate global variables by refactoring the buycomputers method. return the number of computers to buy, update the core site, and pass by value to avoid side effects.

Explore flow control in Java methods, distinguishing parameters and arguments, and see public versus private members, return behavior, and refactoring in a car game example.

Discover how Java operator precedence determines expression evaluation, using addition and multiplication. Learn to use parentheses to enforce the intended order and ensure consistent results.

Explore member selection, aka dot notation, and how post- and pre-increment are evaluated. Recognize operator precedence and why side effects should be avoided in expressions.

Explore using the remainder operator to determine the winner in rock, paper, scissors by mapping constants and applying (value + 1) % 3, then simplify conditions and test operator precedence.

Explore relational and conditional operators, boolean results, assignment operators, and how precedence shapes expressions with concrete code examples and the use of parentheses.

Explore how short circuit evaluation in Java with && and || skips the second operand when the first determines the outcome, preventing errors like divide by zero.

Learn how assignment operators like +=, -=, *=, and /= combine arithmetic with assignment in Java, with examples and guidance on avoiding side effects.

Learn how Java strings work as immutable sequences of Unicode characters. Create and concatenate strings using +, String.format, and printf, and access characters with charAt in a looping example.

Master string indexing and character access in Java by using the charAt method, exploring zero-based indexes, and practicing with for loops and string examples.

Learn how to find substrings with Java's indexOf method by lowercasing input, checking each match, and handling the -1 result when a substring isn't found.

Implement a case-insensitive string search in Java by building indexOfIgnoreCase that lowercases both strings before using indexOf. Learn how equalsIgnoreCase relates to case-insensitive comparison.

Learn how to locate multiple substring matches in java by using lastIndexOf and indexOf with a fromIndex, then iterate with a do-while loop to find all occurrences.

Replace a single occurrence in a string using substring and replaceFirst, via a custom replaceByIndex method, then compare with the built-in replace and replaceAll in Java strings.

Explore the official Java string class documentation to learn essential methods such as contains, indexOf, startsWith, endsWith, trim, split, join, and equals, and understand method overloading.

Explore the stringbuilder class in Java, contrast with immutable strings, and learn how mutability affects memory, references, and replacement methods with start and end indices.

Explore how the equals operator and equals method differ for strings and StringBuilder. Learn to convert StringBuilder to string to compare values rather than references.

Explore StringBuilder operations like append and delete and learn method chaining by returning this, with notes on capacity, ensureCapacity, and indexOf for efficient string manipulation.

Learn to compare a StringBuilder reference after delete with the original, print when they match, and see how to chain delete and append methods while noting searching methods are absent.

Switch from string to StringBuilder for in-place text changes, using toString and toLowerCase, and overload replaceByIndex for StringBuilder input, then compare String and StringBuilder for searches and edits.

Explore the Java course roadmap with upcoming content and continuous learning strategies as the crash course adds regular updates to help you become proficient in Java quickly.

Set up Java from the command line on Windows 10 by configuring JAVA_HOME, updating PATH with the JDK bin path, and verifying with java -version and javac.