Spring Boot | 지식 | Request Header 데이터 조회

package hello.servlet.basic.request;

import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet(name = "requestHeaderServlet", urlPatterns = "/request-header")
public class RequestHeaderServlet extends HttpServlet {

    @Override
    public void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        printStartLine(request);
        printHeaders(request);
        printHeaderUtils(request);
        printEtc(request);
        response.getWriter().write("ok");
    }

    //start line 정보
    private void printStartLine(HttpServletRequest request) {
        System.out.println("--- REQUEST-LINE - start ---");
        System.out.println("request.getMethod() = " + request.getMethod()); //GET
        System.out.println("request.getProtocol() = " + request.getProtocol()); // HTTP/1.1
        System.out.println("request.getScheme() = " + request.getScheme()); //http // http://localhost:8080/request-header
        System.out.println("request.getRequestURL() = " + request.getRequestURL()); // /request-header
        System.out.println("request.getRequestURI() = " + request.getRequestURI()); //username=hi
        System.out.println("request.getQueryString() = " + request.getQueryString());
        System.out.println("request.isSecure() = " + request.isSecure()); //https 사용 유무
        System.out.println("--- REQUEST-LINE - end ---");
        System.out.println();
    }

    private void printHeaders(HttpServletRequest request) {
        System.out.println("--- Headers - start ---");
    /*
      Enumeration<String> headerNames = request.getHeaderNames();
      while (headerNames.hasMoreElements()) {
          String headerName = headerNames.nextElement();
          System.out.println(headerName + ": " + request.getHeader(headerName));
      }
    */
        request.getHeaderNames().asIterator()
                .forEachRemaining(headerName -> System.out.println(headerName + ":" + request.getHeader(headerName)));
        System.out.println("--- Headers - end ---");
        System.out.println();
    }


    //Header 편리한 조회
    private void printHeaderUtils(HttpServletRequest request) {
        System.out.println("--- Header 편의 조회 start ---");
        System.out.println("[Host 편의 조회]");
        System.out.println("request.getServerName() = " + request.getServerName()); //Host 헤더
        System.out.println("request.getServerPort() = " + request.getServerPort()); //Host 헤더 System.out.println();
        System.out.println("[Accept-Language 편의 조회]");
        request.getLocales().asIterator().forEachRemaining(locale -> System.out.println("locale = " + locale));
        System.out.println("request.getLocale() = " + request.getLocale());
        System.out.println();
        System.out.println("[cookie 편의 조회]");
        if (request.getCookies() != null) {
            for (Cookie cookie : request.getCookies()) {
                System.out.println(cookie.getName() + ": " + cookie.getValue());
            }
        }
        System.out.println();
        System.out.println("[Content 편의 조회]");
        System.out.println("request.getContentType() = " + request.getContentType());
        System.out.println("request.getContentLength() = " + request.getContentLength());
        System.out.println("request.getCharacterEncoding() = " + request.getCharacterEncoding());
        System.out.println("--- Header 편의 조회 end ---");
        System.out.println();
    }

    // 기타 정보
    private void printEtc(HttpServletRequest request) { System.out.println("--- 기타 조회 start ---");
        System.out.println("[Remote 정보]");
        System.out.println("request.getRemoteHost() = " + request.getRemoteHost()); //
        System.out.println("request.getRemoteAddr() = " + request.getRemoteAddr()); //
        System.out.println("request.getRemotePort() = " + request.getRemotePort()); //
        System.out.println();
        System.out.println("[Local 정보]");
        System.out.println("request.getLocalName() = " + request.getLocalName()); //
        System.out.println("request.getLocalAddr() = " + request.getLocalAddr()); //
        System.out.println("request.getLocalPort() = " + request.getLocalPort()); //
        System.out.println("--- 기타 조회 end ---");
        System.out.println();
    }

}