abstract class Animal050925 {
    public Animal050925() {
        System.out.print("Animal ");
        makeSound();
    }
    
    abstract void makeSound();
}

class Dog050925 extends Animal050925 {
    public Dog050925() {
        System.out.print("Dog ");
    }
    
    void makeSound() {
        System.out.print("Woof ");
    }
}

public class Task050925 {
    public static void main(String[] args) {
        new Dog050925();
    }
}

replicas: 5  # Не "запусти 5 экземпляров", а "должно быть 5 реплик"

services:
  web:
    image: nginx:alpine
    ports:
      - "8080:80"
  db:
    image: postgres:15
    environment:
      POSTGRES_PASSWORD: example

volumes:
  pgdata:
    driver: local

  volumes:
    - ./data:/var/lib/postgresql/data
  

networks:
  app_net:
    driver: bridge

DB_PASSWORD=secure_password

services:
  db:
    environment:
      POSTGRES_PASSWORD: ${DB_PASSWORD}

services:
  app:
    depends_on:
      - db
  db:
    image: postgres

db:
  image: postgres
  healthcheck:
    test: ["CMD-SHELL", "pg_isready -U postgres"]
    interval: 5s
    timeout: 5s
    retries: 10

  app:
    depends_on:
      db:
        condition: service_healthy
  

├── docker-compose.yml
├── docker-compose.override.yml   # Для dev
└── docker-compose.prod.yml       # Для prod

  docker-compose -f docker-compose.yml -f docker-compose.prod.yml up
  

  # docker-compose.override.yml
  services:
    app:
      environment:
        DEBUG: "true"
      volumes:
        - ./src:/app/src
  

version: '3.8'
services:
  app:
    build: ./app
    ports:
      - "8080:8080"
    environment:
      SPRING_DATASOURCE_URL: jdbc:postgresql://db:5432/mydb
      SPRING_DATASOURCE_PASSWORD: ${DB_PASSWORD}
    depends_on:
      db:
        condition: service_healthy
    networks:
      - app_net

  db:
    image: postgres:15
    environment:
      POSTGRES_DB: mydb
      POSTGRES_PASSWORD: ${DB_PASSWORD}
    volumes:
      - pgdata:/var/lib/postgresql/data
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U postgres"]
      interval: 2s
      timeout: 5s
      retries: 15
    networks:
      - app_net

volumes:
  pgdata:

networks:
  app_net:
    driver: bridge

services:
  kafka:
    image: bitnami/kafka:3.5.1
    container_name: kafka
    ports:
      - "9092:9092"
    environment:
      KAFKA_CFG_NODE_ID: 0
      KAFKA_CFG_PROCESS_ROLES: broker,controller
      KAFKA_CFG_LISTENERS: PLAINTEXT://:9092,CONTROLLER://:9093
      KAFKA_CFG_ADVERTISED_LISTENERS: PLAINTEXT://kafka:9092
      KAFKA_CFG_LISTENER_SECURITY_PROTOCOL_MAP: PLAINTEXT:PLAINTEXT,CONTROLLER:PLAINTEXT
      KAFKA_CFG_CONTROLLER_LISTENER_NAMES: CONTROLLER
      KAFKA_CFG_INTER_BROKER_LISTENER_NAME: PLAINTEXT
    networks:
      - app_net

  app:
    # ... (Java-сервис из предыдущего примера)
    depends_on:
      - kafka

# application.properties
spring.kafka.bootstrap-servers=kafka:9092
spring.kafka.consumer.group-id=my-group

Properties props = new Properties();
props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "kafka:9092");
props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
KafkaProducer<String, String> producer = new KafkaProducer<>(props);

public class Task080925 {
    public static void main(String[] args) {
        Long a = 100L;
        Long b = 100L;
        Long c = 200L;
        Long d = 200L;
        
        System.out.println((a == b) + " " + (c == d));
    }
}