> For the complete documentation index, see [llms.txt](https://sec88.0x88.online/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sec88.0x88.online/programming/java/java-essentials-code-notes.md). # Java Essentials Code Notes ```java import java.util.Scanner; public class HelloJava { public static void main(String[] args) { // Printing System.out.println("Hello World !!\nNew Line !!"); // Variables int score = 6; // Declare and Initialize score = score + 1; // Update variable System.out.println("Your score: " + score); // Your score: 7 double studentGrade = 88.8; String name = "Mosaad Sallam"; System.out.println(name + " : " + studentGrade); // Mosaad Sallam : 88.8 long views = 3_000_000_000L; float price = 50.99F; char answer = 'A'; boolean isRaised = false; double result = 10 % 3; // 1 int x = 1, y; y = ++x; // Postfix x=2 y=2 Score x += 2; // x = x + 2 // Casting in JAVA long a = 5; int b = (int) a; System.out.println(b); // 5 // Salary Program String salaryDetails = "Salary details :" + "\n------------------" + "\nYour base salary : " + a + "\nTaxes : " + b + "\nSalary after taxes : " + (x - y) + "\nIncentive : " + score + "\n--------------------" + "\nNet salary : " + price; System.out.println(salaryDetails); // If-else Statement int number1 = 1; if (number1 > 0) { System.out.println("The number is positive."); } else { System.out.println("The number is not positive."); } System.out.println("Statement outside if...else block"); // Operators // Arithmetic Operators int e = 12, f = 5; System.out.println("a + b = " + (e + f)); System.out.println("a - b = " + (e - f)); System.out.println("a * b = " + (e * f)); System.out.println("a / b = " + (e / f)); System.out.println("a % b = " + (e % f)); // Assignment Operators int g = 4, lol; lol = g; System.out.println("Var using =: " + lol); lol += g; System.out.println("Var using +=: " + lol); lol *= g; System.out.println("Var using *=: " + lol); // Relational Operators int h = 7, j = 11; System.out.println("a is " + a + " and b is " + b); System.out.println(h == j); // false System.out.println(h != j); // true System.out.println(h > j); // false System.out.println(h < j); // true System.out.println(h >= j); // false System.out.println(h <= j); // true // Logical Operators System.out.println((5 > 3) && (8 > 5)); // true System.out.println((5 > 3) && (8 < 5)); // false System.out.println((5 < 3) || (8 > 5)); // true System.out.println((5 > 3) || (8 < 5)); // true System.out.println((5 < 3) || (8 < 5)); // false System.out.println(!(5 == 3)); // true System.out.println(!(5 > 3)); // false // Unary Operators int l = 12, z = 12; int result1, result2; System.out.println("Value of a: " + l); result1 = ++l; System.out.println("After increment: " + result1); System.out.println("Value of b: " + z); result2 = --z; System.out.println("After decrement: " + result2); // Java instanceof Operator String str = "Programiz"; boolean isString; isString = str instanceof String; System.out.println("Is str an object of String? " + isString); // switch-case int num = 44; String size; switch (num) { case 29: size = "Small"; break; case 42: size = "Medium"; break; case 44: size = "Large"; break; case 48: size = "Extra Large"; break; default: size = "Unknown"; break; } System.out.println("Size: " + size); // Getting Input Scanner input = new Scanner(System.in); System.out.print("Enter float: "); float myFloat = input.nextFloat(); System.out.println("Float entered = " + myFloat); System.out.print("Enter double: "); double myDouble = input.nextDouble(); System.out.println("Double entered = " + myDouble); System.out.print("Enter text: "); String myString = input.next(); System.out.println("Text entered = " + myString); // Java Arrays String[] array = new String[100]; double[] data; data = new double[10]; double[] dataArray = new double[10]; int[] ageArray = {12, 4, 5, 2, 5}; // Declare, Initialize, and Access System.out.println("Accessing Elements of Array:"); for (int i = 0; i < ageArray.length; i++) { System.out.println("Element at index " + i + ": " + ageArray[i]); } // Compute Sum and Average of Array Elements int[] numbersArray = {2, -9, 0, 5, 12, -25, 22, 9, 8, 12}; int sumArray = 0; double averageArray; for (int numArray : numbersArray) { sumArray += numArray; } int arrayLength = numbersArray.length; averageArray = ((double) sumArray / arrayLength); System.out.println("Sum = " + sumArray); // Sum = 36 System.out.println("Average = " + averageArray); // Average = 3.6 // Create a 2D array int[][] array2D = { {1, 2, 3}, {4, 5, 6, 9}, {7}, }; System.out.println("Length of row 1: " + array2D[0].length); System.out.println("Length of row 2: " + array2D[1].length); System.out.println("Length of row 3: " + array2D[2].length); // Copying arrays int[] numbersCopy = {1, 2, 3, 4, 5, 6}; int[] positiveNumbers = numbersCopy.clone(); // Copying arrays for (int numCopy : positiveNumbers) { System.out.print(numCopy + ", "); } } } ``` --- # Agent Instructions This documentation is published with GitBook. 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