Ensuring Closeable is closed in Java/Groovy

Closeable.groovy

public class Database {
  
  public void useConnection (Consumer consumer) {
    try (def connection : newConnection()) {
      consumer.accept(connection);
    }
  }
  
  private Connection newConnection () { /*...*/ };
  
}

// Use:
database.useConnection { c ->
  c.executeQuery(...);
}