??

1. ?? ??
2. ?? ?? ?? ??
3. ?? ??? ?? ??? ??
4. ?? ?? ??
5. ?? ?? ??
6. ?? ?? ? ???? ??

?? ??

?? ???? ??????

?? ??? ??? ??? ??? ?? ???? ???? ??? ?????. ??????? ??? ? ?? ??? ???? ?? ?? ? ??? ????? ??? ??? ???? ?? ??? ? ????.

?? ??

1. ??? ???: ??? ??? ???? ??
2. ? ?? ?? ??: ?? ?? ? ?? ???? ???? ??????? ? ??? ?????
3. ??? ???: ??? ?? ?????? ?? ? ?? ??? ?????
4. ??? ??: ??? ??? ???? ?????? ???? ?????

?? ?? ?? ??

?? ??? ???? ?? ??? ??? ??? ?????.

class User {
    private ?Profile $profile = null;
    private int $id;

    public function __construct(int $id) {
        $this->id = $id;
        // Notice that Profile is not loaded here
        echo "User {$id} constructed without loading profile\n";
    }

    public function getProfile(): Profile {
        // Load profile only when requested
        if ($this->profile === null) {
            echo "Loading profile for user {$this->id}\n";
            $this->profile = new Profile($this->id);
        }
        return $this->profile;
    }
}

class Profile {
    private int $userId;
    private array $data;

    public function __construct(int $userId) {
        $this->userId = $userId;
        // Simulate database load
        $this->data = $this->loadProfileData($userId);
    }

    private function loadProfileData(int $userId): array {
        // Simulate expensive database operation
        sleep(1); // Represents database query time
        return ['name' => 'John Doe', 'email' => 'john@example.com'];
    }
}

? ?? ??? ?? ??

1. User ??? ???? ??? ID? ?????
2. Profile ??? getProfile()? ??? ??? ???? ????
3. ???? ???? $profile ??? ?????
4. getProfile()? ?? ?? ??? ??? ????? ?????

?? ??? ?? ??? ??

??? ??? ?? ??? ?? ?? ??? ?? ??? ?????.

interface UserInterface {
    public function getName(): string;
    public function getEmail(): string;
}

class RealUser implements UserInterface {
    private string $name;
    private string $email;
    private array $expensiveData;

    public function __construct(string $name, string $email) {
        $this->name = $name;
        $this->email = $email;
        $this->loadExpensiveData(); // Simulate heavy operation
        echo "Heavy data loaded for {$name}\n";
    }

    private function loadExpensiveData(): void {
        sleep(1); // Simulate expensive operation
        $this->expensiveData = ['some' => 'data'];
    }

    public function getName(): string {
        return $this->name;
    }

    public function getEmail(): string {
        return $this->email;
    }
}

class LazyUserProxy implements UserInterface {
    private ?RealUser $realUser = null;
    private string $name;
    private string $email;

    public function __construct(string $name, string $email) {
        // Store only the minimal data needed
        $this->name = $name;
        $this->email = $email;
        echo "Proxy created for {$name} (lightweight)\n";
    }

    private function initializeRealUser(): void {
        if ($this->realUser === null) {
            echo "Initializing real user object...\n";
            $this->realUser = new RealUser($this->name, $this->email);
        }
    }

    public function getName(): string {
        // For simple properties, we can return directly without loading the real user
        return $this->name;
    }

    public function getEmail(): string {
        // For simple properties, we can return directly without loading the real user
        return $this->email;
    }
}

??? ?? ??

1. UserInterface? ?? ??? ??? ?? ?? ??? ?????? ??? ?????
2. RealUser?? ??? ??? ??? ???? ????
3. LazyUserProxy? ?? ?? ??? ???
4. ???? ??? ???? ?? ??? ?????
5. ??? ??? ????? ?? ??? ? ????

?? ?? ??

?? ????? ??? ?? ??? ?????. ???? ???? ??? ????.

class User {
    private ?Profile $profile = null;
    private int $id;

    public function __construct(int $id) {
        $this->id = $id;
        // Notice that Profile is not loaded here
        echo "User {$id} constructed without loading profile\n";
    }

    public function getProfile(): Profile {
        // Load profile only when requested
        if ($this->profile === null) {
            echo "Loading profile for user {$this->id}\n";
            $this->profile = new Profile($this->id);
        }
        return $this->profile;
    }
}

class Profile {
    private int $userId;
    private array $data;

    public function __construct(int $userId) {
        $this->userId = $userId;
        // Simulate database load
        $this->data = $this->loadProfileData($userId);
    }

    private function loadProfileData(int $userId): array {
        // Simulate expensive database operation
        sleep(1); // Represents database query time
        return ['name' => 'John Doe', 'email' => 'john@example.com'];
    }
}

?? ?? ?? ?? ??

1. LazyLoader? ???? ? ??? ????? ?????? ?? ?????
2. ??? ??? ?? ?? ??? ?????
3. ??? ???? ?? ??? ?????
4. ????? ?? ??? ?????
5. ?? ??? ?? ??? ?? ???? ?????
6. ??? ?????? ??? ?? ?????

?? ?? ??

?? ??? ?? ?? ??(PHP 8)

interface UserInterface {
    public function getName(): string;
    public function getEmail(): string;
}

class RealUser implements UserInterface {
    private string $name;
    private string $email;
    private array $expensiveData;

    public function __construct(string $name, string $email) {
        $this->name = $name;
        $this->email = $email;
        $this->loadExpensiveData(); // Simulate heavy operation
        echo "Heavy data loaded for {$name}\n";
    }

    private function loadExpensiveData(): void {
        sleep(1); // Simulate expensive operation
        $this->expensiveData = ['some' => 'data'];
    }

    public function getName(): string {
        return $this->name;
    }

    public function getEmail(): string {
        return $this->email;
    }
}

class LazyUserProxy implements UserInterface {
    private ?RealUser $realUser = null;
    private string $name;
    private string $email;

    public function __construct(string $name, string $email) {
        // Store only the minimal data needed
        $this->name = $name;
        $this->email = $email;
        echo "Proxy created for {$name} (lightweight)\n";
    }

    private function initializeRealUser(): void {
        if ($this->realUser === null) {
            echo "Initializing real user object...\n";
            $this->realUser = new RealUser($this->name, $this->email);
        }
    }

    public function getName(): string {
        // For simple properties, we can return directly without loading the real user
        return $this->name;
    }

    public function getEmail(): string {
        // For simple properties, we can return directly without loading the real user
        return $this->email;
    }
}

?? ?? ? ???? ??

?? ??

1. ??? ?? ???: ?? ??? ???? ??? ?? ???? ?????
2. ?? ??: ??? ??? ?? ??? ?? ?? ??
3. ???: ?? ?? ??? ??? ?? ??? ??????
4. ???: ?? ?? ????? ?? ?? ???? ?? ???
5. ?? ????: ?? ??? ??????? ??? ??? ???????

???? ??

1. ??? ??: ???? ?? ?? ?? ??? ?? ??? ???? ??
2. ?? ???: ?? ??? ??? ???? ??
3. ???? ?? ??: ???? ?? ?? ?? ?? ??
4. ??? ???: ?? ?? ??? ???? ??
5. ???? ?? ??: ??? ??? ??? ???? ??

?? ?? ??

?? ??? ???? ?? ??

• ?? ???? ?? ?? ??
• ????? ??? ?? ?? ??? ??? ??
• ?? ??? ?????? ?? ? ?? ??
• ????? ?? ??? ???? ?? ???

?? ??? ???? ??? ? ??

• ?? ??? ??
• ?? ?? ??? ??
• ??? ??? ??? ??
• ?? ??? ???? ???? ? ? ??

? ??? ?? ?? ? ?? ??? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!