カスタム サーブレットはどのようにして複数のコンテナに静的 Web コンテンツを効率的に提供できるのでしょうか?

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class StaticContentServlet extends HttpServlet {

  private Path filePath;

  @Override
  public void init() throws ServletException {
    super.init();
    String filePathString = getServletConfig().getInitParameter("filePath");
    if (filePathString == null) {
      throw new ServletException("Missing filePath init parameter");
    }
    filePath = Paths.get(filePathString);
  }

  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
    String path = request.getRequestURI().substring(request.getContextPath().length());
    File file = filePath.resolve(path).toFile();
    if (file.exists()) {
      response.setStatus(HttpServletResponse.SC_OK);
      response.setContentType(Files.probeContentType(file.toPath()));
      if (request.getDateHeader("If-Modified-Since") <= file.lastModified()) {
        response.setDateHeader("Last-Modified", file.lastModified());
      } else {
        response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
        return;
      }
      Files.copy(file.toPath(), response.getOutputStream());
    } else {
      response.sendError(HttpServletResponse.SC_NOT_FOUND);
    }
  }
}

<servlet-mapping>
  <servlet-name>StaticContentServlet</servlet-name>
  <url-pattern>/static/*</url-pattern>
</servlet-mapping>