18. జావా పాలిమార్ఫిజమ్, Method Overriding & Dynamic Binding (Polymorphism Mastery)

public class DynamicMethodDispatchDemo {

    public static class CloudStorageService {
        public void uploadFile(String fileName) {
            System.out.println("📦 Standard Blob Upload: " + fileName);
        }
    }

    public static class S3StorageService extends CloudStorageService {
        @Override
        public void uploadFile(String fileName) {
            System.out.println("☁️ [AWS S3] Uploading multipart chunk to s3://media-bucket/" + fileName);
        }
    }

    public static class AzureBlobStorageService extends CloudStorageService {
        @Override
        public void uploadFile(String fileName) {
            System.out.println("🔷 [Azure Blob] Uploading block blob to container/cdn/" + fileName);
        }
    }

    public static class GoogleCloudStorageService extends CloudStorageService {
        @Override
        public void uploadFile(String fileName) {
            System.out.println("🇬 [Google Cloud] Streaming object to gs://ai-artifacts/" + fileName);
        }
    }

    public static void main(String[] args) {
        System.out.println("=================================================");
        System.out.println("⚡ RUNTIME POLYMORPHISM & DYNAMIC DISPATCH DEMO");
        System.out.println("=================================================
");

        // Polymorphic Array: Parent reference holding different child instances
        CloudStorageService[] storageProviders = {
            new S3StorageService(),
            new AzureBlobStorageService(),
            new GoogleCloudStorageService()
        };

        String testFile = "telemetry_logs_2026.parquet";

        System.out.println("Iterating polymorphic array without switch/case statements:");
        for (CloudStorageService provider : storageProviders) {
            // JVM resolves exact method at runtime via vtable!
            provider.uploadFile(testFile);
        }

        System.out.println("
=================================================");
        System.out.println("✅ JVM Dynamically Dispatched each method at runtime!");
        System.out.println("=================================================");
    }
}

public class PatternMatchingAndDowncastingDemo {

    public static class SmartDevice {
        String deviceName;
        SmartDevice(String name) { this.deviceName = name; }
        public void getStatus() { System.out.println("Device: " + deviceName + " is ONLINE"); }
    }

    public static class SmartThermostat extends SmartDevice {
        double currentTempCelsius;
        SmartThermostat(String name, double temp) {
            super(name);
            this.currentTempCelsius = temp;
        }
        public void adjustTemperature(double target) {
            System.out.printf("  🌡️ Adjusting %s from %.1f°C to %.1f°C%n", deviceName, currentTempCelsius, target);
        }
    }

    public static class SecurityCamera extends SmartDevice {
        int resolutionPixels;
        SecurityCamera(String name, int res) {
            super(name);
            this.resolutionPixels = res;
        }
        public void triggerNightVision(boolean enable) {
            System.out.println("  📹 Camera " + deviceName + " Night Vision set to: " + enable);
        }
    }

    public static void inspectDevicePolymorphically(SmartDevice dev) {
        dev.getStatus(); // Base polymorphic call

        // Modern Java 16+ Pattern Matching for instanceof
        if (dev instanceof SmartThermostat thermo) {
            // 'thermo' is already safely cast and in scope!
            thermo.adjustTemperature(22.5);
        } else if (dev instanceof SecurityCamera cam) {
            // 'cam' is safely cast and in scope!
            cam.triggerNightVision(true);
        }
        System.out.println();
    }

    public static void main(String[] args) {
        System.out.println("=================================================");
        System.out.println("🔍 MODERN PATTERN MATCHING FOR INSTANCEOF DEMO");
        System.out.println("=================================================
");

        SmartDevice d1 = new SmartThermostat("LivingRoom-AC", 28.0); // Upcasting
        SmartDevice d2 = new SecurityCamera("FrontGate-Cam", 4096);   // Upcasting

        inspectDevicePolymorphically(d1);
        inspectDevicePolymorphically(d2);

        System.out.println("=================================================");
        System.out.println("✅ Zero ClassCastExceptions encountered!");
        System.out.println("=================================================");
    }
}

public class CloudMediaStreamRendererEngine {

    // Base Abstract Media Asset
    public static class MediaStreamAsset {
        private final String assetId;
        private final String title;
        private final long fileSizeBytes;

        public MediaStreamAsset(String id, String title, long bytes) {
            this.assetId = id;
            this.title = title;
            this.fileSizeBytes = bytes;
        }

        // Polymorphic method to be overridden
        public void renderForStreaming() {
            System.out.printf("🎞️ Rendering Base Asset [%s: '%s'] (%,d bytes)...%n", assetId, title, fileSizeBytes);
        }

        public String getAssetId() { return assetId; }
        public String getTitle() { return title; }
    }

    // Subclass 1: 4K HDR Video Stream
    public static class HdrVideoStream extends MediaStreamAsset {
        private final String codec;
        private final int framerateFps;

        public HdrVideoStream(String id, String title, long bytes, String codec, int fps) {
            super(id, title, bytes);
            this.codec = codec;
            this.framerateFps = fps;
        }

        @Override
        public void renderForStreaming() {
            super.renderForStreaming();
            System.out.printf("   🎬 Hardware Transcoding [%s @ %d FPS] with Dolby Vision Pipeline%n",
                    codec, framerateFps);
        }
    }

    // Subclass 2: Lossless Dolby Atmos Audio Stream
    public static class DolbyAtmosAudioStream extends MediaStreamAsset {
        private final int audioChannels;
        private final int bitrateKbps;

        public DolbyAtmosAudioStream(String id, String title, long bytes, int channels, int bitrate) {
            super(id, title, bytes);
            this.audioChannels = channels;
            this.bitrateKbps = bitrate;
        }

        @Override
        public void renderForStreaming() {
            super.renderForStreaming();
            System.out.printf("   🎧 Spatial Audio Processing [%d Channels @ %d kbps High-Res]%n",
                    audioChannels, bitrateKbps);
        }
    }

    public static void main(String[] args) {
        System.out.println("=================================================");
        System.out.println("📺 CLOUD MEDIA STREAMING & TRANSCODING PIPELINE");
        System.out.println("=================================================
");

        MediaStreamAsset[] broadcastPlaylist = {
            new HdrVideoStream("VID-801", "Interstellar Travel 4K", 4200000000L, "HEVC/H.265", 60),
            new DolbyAtmosAudioStream("AUD-402", "Symphony No. 9 Spatial", 185000000L, 8, 768),
            new HdrVideoStream("VID-905", "Cyberpunk Future Night 8K", 8900000000L, "AV1", 120)
        };

        System.out.println("🚀 Transcoding Broadcast Playlist Polymorphically:
");
        for (MediaStreamAsset item : broadcastPlaylist) {
            item.renderForStreaming(); // Polymorphic dispatch via vtable!
            System.out.println("-------------------------------------------------");
        }

        System.out.println("
=================================================");
        System.out.println("✅ All heterogeneous streams transcoded without conditional branching!");
        System.out.println("=================================================");
    }
}