public class Config {
    public static final String API_URL = "https://api.myapp.com/";
    public static final int MAX_LOGIN_ATTEMPTS = 5;
}

System.out.println("URL: " + Config.API_URL);
if (loginAttempts > Config.MAX_LOGIN_ATTEMPTS) {
    System.out.println("Too many failed attempts.");
}

public class Config {
    public final String API_URL = "https://api.myapp.com/";
}

Config cfg = new Config();
System.out.println(cfg.API_URL); // غیربهینه و غیرضروری

System.out.println(Config.API_URL); // ساده و مستقیم

public static final String DATABASE_NAME = "main.db";

#کاربرـپیشرفته

🆔 @javapro_ir
🆔 @group_javapro

final int x = 10;
x = 20; //  خطا

public class Example {
    public static void main(String[] args) {
        int number = 5; // not declared as final
        Runnable r = () -> System.out.println(number); //  مجاز چون effectively final است
        r.run();
    }
}

int number = 5;
number++; //  اکنون دیگر effectively final نیست
Runnable r = () -> System.out.println(number); //  خطای کامپایل

int[] counter = {0};
Runnable r = () -> counter[0]++;

#کاربرـحرفهـای

🆔 @javapro_ir
🆔 @group_javapro

public class ClosureExample {
    public static void main(String[] args) {
        int base = 10;

        Function<Integer, Integer> adder = (value) -> value + base;

        System.out.println(adder.apply(5)); // خروجی: 15
    }
}

int base = 10;
base++; //  باعث خطا می‌شود
Function<Integer, Integer> adder = (value) -> value + base;

public class MultiplierFactory {
    public static Function<Integer, Integer> createMultiplier(int factor) {
        return (value) -> value * factor;
    }

    public static void main(String[] args) {
        Function<Integer, Integer> timesTwo = createMultiplier(2);
        Function<Integer, Integer> timesThree = createMultiplier(3);

        System.out.println(timesTwo.apply(5)); // خروجی: 10
        System.out.println(timesThree.apply(5)); // خروجی: 15
    }
}

#کاربرـحرفهـای

🆔 @javapro_ir
🆔 @group_javapro