Configuration और Profiles

import java.util.*;public class Main {
  public static void main(String[] args) {
    Properties props = new Properties();
    props.setProperty("server.port", "8080"); // pretend from application.properties
    System.out.println("Server will run on port: " + props.getProperty("server.port"));
  }
}

public class Main {
  public static void main(String[] args) {
    String profile = "dev"; // pretend active profile
    if ("dev".equals(profile)) {
      System.out.println("Using H2 in-memory DB for development");
    } else if ("prod".equals(profile)) {
      System.out.println("Using PostgreSQL DB for production");
    }
  }
}

public class Main {
  public static void main(String[] args) {
    String profile = "test"; // pretend active profile
    if ("test".equals(profile)) {
      System.out.println("Loading fake email sender for testing");
    } else {
      System.out.println("Loading real email sender");
    }
  }
}