Constructor Chaining

public class Employee {
    // Constructor الافتراضي
    Employee() {
        this(2023); // استدعاء Constructor مع معلمة واحدة
        System.out.println("In Default Constructor Of Employee Class");
    }

    // Constructor مع معلمة واحدة
    Employee(int id) {
        this("Ankush"); // استدعاء Constructor مع معلمة نصية
        System.out.println("In Parameterized Constructor with Integer Parameter: " + id);
    }

    // Constructor مع معلمة نصية
    Employee(String name) {
        System.out.println("In Parameterized Constructor With String Parameter: " + name);
    }

    public static void main(String[] args) {
        Employee emp = new Employee();
    }
}

In Parameterized Constructor With String Parameter: Ankush
In Parameterized Constructor with Integer Parameter: 2023
In Default Constructor Of Employee Class
Constructor Overloading

public class Student {
    private String name;
    private int age;

    // Constructor الافتراضي
    public Student() {
        name = "Unknown";
        age = 0;
    }

    // Constructor مع معلمة واحدة
    public Student(String name) {
        this.name = name;
        age = 0;
    }

    // Constructor مع معلمتين
    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public void display() {
        System.out.println("Name: " + name + ", Age: " + age);
    }
}

اعتقد كافيي بس جان ضروري انزلهن لان هذا ماده الامتحان مال باجر
اذا سمحت فرصه الي بعشوي انزل امثله اكثر
هذا فقط امثله الملزمه

سؤال المختبر القادم للهياكل علوم صباحي /
//
اكتب برنامج يقرء مصفوفه احاديه ومصفوفة ثنائيه ومصفوفه ثلاثيه ومصفوفه مثلثه تكون 4*4
وتكون بيها عمليات خاصه للجزء العلوي عمليات خاصه للجزء السفلي
ثم يطلب من المستخدم اختيار نوع المصفوفه ووحجم المصفوفه وعناصر المجموعه ثم طباعتها واجراء 5 عمليات عليها ويبقى يطلب من المستخدم اجراء عمليات لحين طلب المستخدم الخروج من العمليات

import java.util.Scanner;

public class    hmd{
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        boolean exit = false;

        while (!exit) {
            System.out.println("اختر نوع المصفوفة: 1. أحادية 2. ثنائية 3. ثلاثية 4. مثلثية 5. خروج");
            int choice = scanner.nextInt();

            switch (choice) {
                case 1:
                   
                    System.out.println(" enter size :");
                    int size = scanner.nextInt();
                    int[] array = new int[size];
                    System.out.println("أدخل العناصر:");
                    for (int i = 0; i < size; i++) {
                        array[i] = scanner.nextInt();
                    }
                    printArray(array);
                    arrayD1(array);
                    break;

                case 2:
                   
                    System.out.println(" enter r:");
                    int rows = scanner.nextInt();
                    System.out.println(" enter c:");
                    int cols = scanner.nextInt();
                    int[][] matrix = new int[rows][cols];
                    System.out.println("أدخل العناصر:");
                    for (int i = 0; i < rows; i++) {
                        for (int j = 0; j < cols; j++) {
                            matrix[i][j] = scanner.nextInt();
                        }
                    }
                    printArray(matrix);
                    arrayD2(matrix);
                    break;

                case 3:
             
                    System.out.println(" enter l :");
                    int layers = scanner.nextInt();
                    System.out.println(" enter r :");
                    int threesRows = scanner.nextInt();
                    System.out.println(" enter c :");
                    int threesCols = scanner.nextInt();
                    int[][][] threeDMatrix = new int[layers][threesRows][threesCols];
                    System.out.println("أدخل العناصر:");
                    for (int i = 0; i < layers; i++) {
                        for (int j = 0; j < threesRows; j++) {
                            for (int k = 0; k < threesCols; k++) {
                                threeDMatrix[i][j][k] = scanner.nextInt();
                            }
                        }
                    }
                    printArray(threeDMatrix);
                    arrayD3(threeDMatrix);
                    break;

                case 4:
                  
                    int[][] triangularMatrix = new int[4][4];
                    System.out.println("اختر الجزء: 1. علوي 2. سفلي");
                    int part = scanner.nextInt();

                    if (part == 1) {
                 
                        System.out.println("أدخل العناصر للجزء العلوي:");
                        for (int i = 0; i < 4; i++) {
                            for (int j = i; j < 4; j++) {
                                triangularMatrix[i][j] = scanner.nextInt();
                            }
                        }
                    } else if (part == 2) {
                 
                        System.out.println("أدخل العناصر للجزء السفلي:");
                        for (int i = 0; i < 4; i++) {
                            for (int j = 0; j <= i; j++) {
                                triangularMatrix[i][j] = scanner.nextInt();
                            }
                        }
                    } else {
                        System.out.println("اختيار غير صالح.");
                        break;
                    }
                    printArray(triangularMatrix);
                    arrayTriangular(triangularMatrix);
                    break;

                case 5:
                    exit = true;
                    System.out.println("تم الخروج من البرنامج.");
                    break;

                default:
                    System.out.println("اختيار غير صالح.");
            }
        }

       
    }

private static void arrayD1(int[] array) {
        boolean backToMenu = false;
        while (!backToMenu) {
            printArray(array);
            System.out.println("اختر عملية:");
            System.out.println("1. sum ");
            System.out.println("2. avg ");
            System.out.println("3. max ");
            System.out.println("4. min ");
            System.out.println("5. ضرب العناصر في 2");
            System.out.println("6. العودة إلى القائمة الرئيسية");

            int operation = new Scanner(System.in).nextInt();
            switch (operation) {
                case 1:
                    System.out.println(" sum : " + sum(array));
                    break;
                case 2:
                    System.out.println(" avg : " + average(array));
                    break;
                case 3:
                    System.out.println(" max : " + max(array));
                    break;
                case 4:
                    System.out.println(" min : " + min(array));
                    break;
                case 5:
                    multiplyByTwo(array);
                    break;
                case 6:
                    backToMenu = true;
                    break;
                default:
                    System.out.println("اختيار غير صالح!");
            }
        }
    }

 
    private static void arrayD2(int[][] matrix) {
        boolean backToMenu = false;
        while (!backToMenu) {
            printArray(matrix);
            System.out.println("اختر عملية:");
            System.out.println("1. sum ");
            System.out.println("2. avg ");
            System.out.println("3. max ");
            System.out.println("4. min ");
            System.out.println("5. ضرب العناصر في 2");
            System.out.println("6. العودة إلى القائمة الرئيسية");

            int operation = new Scanner(System.in).nextInt();
            switch (operation) {
                case 1:
                    System.out.println(" sum : " + sum(matrix));
                    break;
                case 2:
                    System.out.println(" avg : " + average(matrix));
                    break;
                case 3:
                    System.out.println(" max : " + max(matrix));
                    break;
                case 4:
                    System.out.println(" min : " + min(matrix));
                    break;
                case 5:
                    multiplyByTwo(matrix);
                    break;
                case 6:
                    backToMenu = true;
                    break;
                default:
                    System.out.println("اختيار غير صالح!");
            }
        }
    }

 
    private static void arrayD3(int[][][] matrix) {
        boolean backToMenu = false;
        while (!backToMenu) {
            printArray(matrix);
            System.out.println("اختر عملية:");
            System.out.println("1. sum ");
            System.out.println("2. avg ");
            System.out.println("3. max ");
            System.out.println("4. min ");
            System.out.println("5. ضرب العناصر في 2");
            System.out.println("6. العودة إلى القائمة الرئيسية");

            int operation = new Scanner(System.in).nextInt();
            switch (operation) {
                case 1:
                    System.out.println(" sum : " + sum(matrix));
                    break;
                case 2:
                    System.out.println(" avg : " + average(matrix));
                    break;
                case 3:
                    System.out.println(" max : " + max(matrix));
                    break;
                case 4:
                    System.out.println(" min : " + min(matrix));
                    break;
                case 5:
                    multiplyByTwo(matrix);
                    break;
                case 6:
                    backToMenu = true;
                    break;
                default:
                    System.out.println("اختيار غير صالح!");
            }
        }
    }

private static void arrayTriangular(int[][] matrix) {
        boolean backToMenu = false;
        while (!backToMenu) {
            printArray(matrix);
            System.out.println("اختر عملية:");
            System.out.println("1. sum ");
            System.out.println("2. avg ");
            System.out.println("3. max ");
            System.out.println("4. min ");
            System.out.println("5. ضرب العناصر في 2");
            System.out.println("6. العودة إلى القائمة الرئيسية");

            int operation = new Scanner(System.in).nextInt();
            switch (operation) {
                case 1:
                    System.out.println(" sum : " + sum(matrix));
                    break;
                case 2:
                    System.out.println(" avg : " + average(matrix));
                    break;
                case 3:
                    System.out.println(" max : " + max(matrix));
                    break;
                case 4:
                    System.out.println(" min : " + min(matrix));
                    break;
                case 5:
                    multiplyByTwo(matrix);
                    break;
                case 6:
                    backToMenu = true;
                    break;
                default:
                    System.out.println("اختيار غير صالح!");
            }
        }
    }

  
    private static int sum(int[] array) {
        int total = 0;
        for (int i = 0; i < array.length; i++) {
            total += array[i];
        }
        return total;
    }

    private static double average(int[] array) {
        return (double) sum(array) / array.length;
    }

    private static int max(int[] array) {
        int max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (array[i] > max) {
                max = array[i];
            }
        }
        return max;
    }

    private static int min(int[] array) {
        int min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (array[i] < min) {
                min = array[i];
            }
        }
        return min;
    }

    private static int sum(int[][] matrix) {
        int total = 0;
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                total += matrix[i][j];
            }
        }
        return total;
    }

    private static double average(int[][] matrix) {
        int count = 0;
        int total = sum(matrix);
        for (int i = 0; i < matrix.length; i++) {
            count += matrix[i].length;
        }
        return (double) total / count;
    }

    private static int max(int[][] matrix) {
        int max = matrix[0][0];
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                if (matrix[i][j] > max) {
                    max = matrix[i][j];
                }
            }
        }
        return max;
    }

    private static int min(int[][] matrix) {
        int min = matrix[0][0];
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                if (matrix[i][j] < min) {
                    min = matrix[i][j];
                }
            }
        }
        return min;
    }

    private static int sum(int[][][] matrix) {
        int total = 0;
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                for (int k = 0; k < matrix[i][j].length; k++) {
                    total += matrix[i][j][k];
                }
            }
        }
        return total;
    }

    private static double average(int[][][] matrix) {
        int count = 0;
        int total = sum(matrix);
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                count += matrix[i][j].length;
            }
        }
        return (double) total / count;
    }

private static int max(int[][][] matrix) {
        int max = matrix[0][0][0];
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                for (int k = 0; k < matrix[i][j].length; k++) {
                    if (matrix[i][j][k] > max) {
                        max = matrix[i][j][k];
                    }
                }
            }
        }
        return max;
    }

    private static int min(int[][][] matrix) {
        int min = matrix[0][0][0];
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                for (int k = 0; k < matrix[i][j].length; k++) {
                    if (matrix[i][j][k] < min) {
                        min = matrix[i][j][k];
                    }
                }
            }
        }
        return min;
    }

 
    private static void printArray(int[] array) {
        System.out.print("المصفوفة: ");
        for (int i = 0; i < array.length; i++) {
            System.out.print(array[i] + " ");
        }
        System.out.println();
    }

    private static void printArray(int[][] matrix) {
        System.out.println("المصفوفة:");
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                System.out.print(matrix[i][j] + " ");
            }
            System.out.println();
        }
    }

    private static void printArray(int[][][] matrix) {
        System.out.println("المصفوفة:");
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                for (int k = 0; k < matrix[i][j].length; k++) {
                    System.out.print(matrix[i][j][k] + " ");
                }
                System.out.println();
            }
            System.out.println();
        }
    }

   
    private static void multiplyByTwo(int[] array) {
        for (int i = 0; i < array.length; i++) {
            array[i] *= 2;
        }
        printArray(array);
    }

 
    private static void multiplyByTwo(int[][] matrix) {
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                matrix[i][j] *= 2;
            }
        }
        printArray(matrix);
    }

 
    private static void multiplyByTwo(int[][][] matrix) {
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[i].length; j++) {
                for (int k = 0; k < matrix[i][j].length; k++) {
                    matrix[i][j][k] *= 2;
                }
            }
        }
        printArray(matrix);
    }
}

وجان نخلص المصفوفات هذا اخر مختبر ناخذها

import java.util.Locale;
import java.util.Scanner;

public class hmd2 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter a string: ");
        String input = scanner.nextLine();

        boolean running = true;

        while (running) {
            System.out.println("\nChoose an operation:");
            System.out.println("1. Get a character at a specific index (charAt)");
            System.out.println("2. Get the length of the string (length)");
            System.out.println("3. Create a substring from a start index (substring)");
            System.out.println("4. Create a substring from start to end indices (substring)");
            System.out.println("5. Compare the string with another string (equals)");
            System.out.println("6. Check if the string is empty (isEmpty)");
            System.out.println("7. Concatenate strings (concat)");
            System.out.println("8. Replace a character with another (replace)");
            System.out.println("9. Split the string into words (split)");
            System.out.println("10. Split the string into words with a limit (split with limit)");
            System.out.println("11. Get the string from the constant pool (intern)");
            System.out.println("12. Find the index of a character (indexOf)");
            System.out.println("13. Find the index of a character from a specific position (indexOf with start index)");
            System.out.println("14. Find the index of a substring (indexOf substring)");
            System.out.println("15. Find the index of a substring from a specific position (indexOf substring with start index)");
            System.out.println("16. Convert the string to lowercase (toLowerCase)");
            System.out.println("17. Convert the string to lowercase with locale (toLowerCase with Locale)");
            System.out.println("18. Convert the string to uppercase (toUpperCase)");
            System.out.println("19. Convert the string to uppercase with locale (toUpperCase with Locale)");
            System.out.println("20. Trim whitespace from the string (trim)");
            System.out.println("21. Exit");
            System.out.print("Enter your choice: ");

            int choice = scanner.nextInt();
            scanner.nextLine();

switch (choice) {
                case 1:
                    System.out.print("Enter the index: ");
                    int index = scanner.nextInt();
                    if (index >= 0 && index < input.length()) {
                        System.out.println("Character at index " + index + " is: " + input.charAt(index));
                    } else {
                        System.out.println("Invalid index.");
                    }
                    break;
                case 2:
                    System.out.println("Length of the string: " + input.length());
                    break;
                case 3:
                    System.out.print("Enter the starting index: ");
                    int start = scanner.nextInt();
                    if (start >= 0 && start < input.length()) {
                        System.out.println("Substring: " + input.substring(start));
                    } else {
                        System.out.println("Invalid start index.");}
                    break;
                case 4:
                    System.out.print("Enter the starting index: ");
                    start = scanner.nextInt();
                    System.out.print("Enter the ending index (exclusive): ");
                    int end = scanner.nextInt();
                    if (start >= 0 && end <= input.length() && start < end) {
                        System.out.println("Substring: " + input.substring(start, end));
                    } else {
                        System.out.println("Invalid indices.");
                    }
                    break;
                case 5:
                    System.out.print("Enter another string to compare: ");
                    String another = scanner.nextLine();
                    System.out.println("Strings are equal: " + input.equals(another));
                    break;
                case 6:
                    System.out.println(input.isEmpty() ? "The string is empty." : "The string is not empty.");
                    break;
                case 7:
                    System.out.print("Enter another string to concatenate: ");
                    String secondInput = scanner.nextLine();
                    System.out.println("Concatenated string: " + input.concat(secondInput));
                    break;
                case 8:
                    System.out.print("Enter the character to replace: ");
                    char oldChar = scanner.next().charAt(0);
                    System.out.print("Enter the new character: ");
                    char newChar = scanner.next().charAt(0);
                    input = input.replace(oldChar, newChar);
                    System.out.println("Updated string: " + input);
                    break;
                case 9:
                    String[] words = input.split(" ");
                    System.out.println("Words:");
                    for (String word : words) {
                        System.out.println(word);
                    }
                    break;
                case 10:
                    System.out.print("Enter the maximum number of parts: ");
                    int limit = scanner.nextInt();
                    String[] parts = input.split(" ", limit);
                    System.out.println("Parts:");
                    for (String part : parts) {
                        System.out.println(part);
                    }
                    break;
                case 11:
                    input = input.intern();
                    System.out.println("The string is now stored in the constant pool.");
                    break;

case 12:
                    System.out.print("Enter the character to search for: ");
                    char searchChar = scanner.next().charAt(0);
                    int position = input.indexOf(searchChar);
                    System.out.println(position != -1 ? "Found at position: " + position : "Character not found.");
                    break;
                case 13:
                    System.out.print("Enter the character to search for: ");
searchChar = scanner.next().charAt(0);
                    System.out.print("Enter the starting index for the search: ");
                    int fromIndex = scanner.nextInt();
                    position = input.indexOf(searchChar, fromIndex);
                    System.out.println(position != -1 ? "Found at position: " + position : "Character not found.");
                    break;
                case 14:
                    System.out.print("Enter the substring to search for: ");
                    String substring = scanner.nextLine();
                    position = input.indexOf(substring);
                    System.out.println(position != -1 ? "Found at position: " + position : "Substring not found.");
                    break;
                case 15:
                    System.out.print("Enter the substring to search for: ");
                    substring = scanner.nextLine();
                    System.out.print("Enter the starting index for the search: ");
                    fromIndex = scanner.nextInt();
                    position = input.indexOf(substring, fromIndex);
                    System.out.println(position != -1 ? "Found at position: " + position : "Substring not found.");
                    break;
                case 16:
                    System.out.println("String in lowercase: " + input.toLowerCase());
                    break;
                case 17:
                    System.out.println("String in lowercase (with locale): " + input.toLowerCase(Locale.getDefault()));
                    break;
                case 18:
                    System.out.println("String in uppercase: " + input.toUpperCase());
                    break;
                case 19:
                    System.out.println("String in uppercase (with locale): " + input.toUpperCase(Locale.getDefault()));
                    break;
                case 20:
                    System.out.println("Trimmed string: '" + input.trim() + "'");
                    break;
                case 21:
                    System.out.println("Exiting the program...");
                    running = false;
                    break;
                default:
                    System.out.println("Invalid choice. Please try again.");}}}}

✅لخطوة الأولى: المقدمة إلى البرمجة كائنية التوجه (OOP

✅الخطوه الثانيه:
راح نكتب اول برنامج بالoop وويشرحه بالتفصيل الممل واخر شي راح يشرح Access modifiers
وتعتبر من اهم اساسيات oop

لحد لهنا ضروري تفهمهن حتلو تعيد الشرح اكثر من مره وكلش عادي اذا مافهمت مره ومرتين لان ماده جديده فه اكيد ماتكون سهله الفهم

✅الخطوه الثالثه
راح يشرح .
Constructor
بالانواعه الاربعه مع امثله
و
Method Overloading

✅ الخطوه الرابعه ونووب اخذنا
static keywords
هنه وانواعه مع امثله

✅الخطوه الخامسه
واخر موضوع راح ناخذه بالكورس الاول وهوه
الوراثه
inheritance

هذا مسار يخص كلشي اخذنا والشرح كلش مقارب للملازم تكدرون تعتمدون عليه واكيد راح ننزل امثله بكل المواضيع بالايام الجايه وضروري ادرسون لان مابقه شي عن نهايه الكورس الاول والماده لحد الان زينه

واكيد لو لكيت شرح افضل راح انزله الكم

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