3단계 리팩토링 리뷰 부탁드립니다.

src/main/java/controller/CreateUserController.java

@@ -12,12 +12,17 @@ public class CreateUserController extends AbstractController {
 
     @Override
     public void doPost(HttpRequest request, HttpResponse response) {
+        User user = getUserFrom(request);
+        DataBase.addUser(user);
+        response.sendRedirect("/index.html");
+        log.debug("{}님이 회원가입에 성공하셨습니다.", user.getUserId());
+    }
+
+    private User getUserFrom(HttpRequest request) {
         String userId = request.getParameter("userId");
         String password = request.getParameter("password");
         String name = request.getParameter("name");
         String email = request.getParameter("email");
-        DataBase.addUser(new User(userId, password, name, email));
-        response.sendRedirect("/index.html");
-        log.debug("{}님이 회원가입에 성공하셨습니다.", userId);
+        return new User(userId, password, name, email);
     }
 }

src/main/java/controller/ListUserController.java

@@ -1,6 +1,7 @@
 package controller;
 
 import db.DataBase;
+import db.SessionDataBase;
 import model.User;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -19,44 +20,55 @@ public class ListUserController extends AbstractController {
 
     @Override
     public void doGet(HttpRequest request, HttpResponse response) {
-        String cookies = request.getHeader("Cookie");
-        Map<String, String> cookieStringMap = HttpRequestUtils.parseCookies(cookies);
-        log.info("Cookie: {}", cookieStringMap.toString());
-        if (cookieStringMap.get("logined").equals("false")) {
+        String sessionId = request.getHeader("Cookie");
+        if (!isLogin(sessionId)) {
             response.sendRedirect("/user/login.html");
         } else {
-            String url = "/user/list.html";
-            byte[] body = new byte[0];
-            try {
-                body = Files.readAllBytes(new File("./webapp" + url).toPath());
-            } catch (IOException e) {
-                e.printStackTrace();
-            }
-            String bodyStr = new String(body);
-            int tbodyIndex = bodyStr.indexOf("<tbody>");
-            log.info("bodyStr : {}", bodyStr.substring(0, tbodyIndex + 7));
-
-            StringBuilder result = new StringBuilder(bodyStr.substring(0, tbodyIndex + 7));
-            Collection<User> users = DataBase.findAll();
-            int id = 0;
-            for (User user : users) {
-                id++;
-                result.append("<tr><th scope=\"row\">")
-                        .append(id).append("</th> <td>")
-                        .append(user.getUserId()).append("</td> <td>")
-                        .append(user.getName()).append("</td> <td>")
-                        .append(user.getEmail()).append("</td> <td>")
-                        .append("<a href=\"#\" class=\"btn btn - success\" role=\"button\">수정</a></td>");
-            }
-            result.append(bodyStr.substring(tbodyIndex + 7));
-            log.info("result: {}", result.toString());
-            response.response200Header(result.toString().getBytes().length, "text/html");
-            response.responseBody(result.toString().getBytes());
+            String body = getBody("/user/list.html");
+            int tbodyIndex = body.indexOf("<tbody>");
+            String result = addUserList(body, tbodyIndex).toString();
+            response.forwardBody(result);
         }
     }
 
-    public boolean isLogin(String id) {
+    private boolean isLogin(String id) {
+        Map<String, String> cookieStringMap = HttpRequestUtils.parseCookies(id);
+        log.info("Cookie: {}", cookieStringMap.toString());
+        return SessionDataBase.isLoginUser(cookieStringMap.get("JSESSIONID"));
+    }
+
+    private String getBody(String url) {
+        byte[] body = new byte[0];
+        try {
+            body = Files.readAllBytes(new File("./webapp" + url).toPath());
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        return new String(body);
+    }
+
+    private StringBuilder processUserList(String body, int tbodyIndex) {
+        StringBuilder result = new StringBuilder(body.substring(0, tbodyIndex + 7));
+        Collection<User> users = DataBase.findAll();
+        int id = 0;
+        for (User user : users) {
+            id++;
+            result.append("<tr><th scope=\"row\">")
+                    .append(id)
+                    .append("</th> <td>")
+                    .append(user.getUserId())
+                    .append("</td> <td>")
+                    .append(user.getName())
+                    .append("</td> <td>")
+                    .append(user.getEmail())
+                    .append("</td> <td>")
+                    .append("<a href=\"#\" class=\"btn btn - success\" role=\"button\">수정</a></td>");
+        }
+        return result;
+    }
 
-        return false;
+    private StringBuilder addUserList(String body, int tbodyIndex) {
+        StringBuilder result = processUserList(body, tbodyIndex);
+        return result.append(body.substring(tbodyIndex + 7));
     }
 }

src/main/java/controller/LoginController.java

@@ -1,12 +1,15 @@
 package controller;
 
 import db.DataBase;
+import db.SessionDataBase;
 import model.User;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import webserver.HttpRequest;
 import webserver.HttpResponse;
 
+import java.util.UUID;
+
 public class LoginController extends AbstractController {
     private static final Logger log = LoggerFactory.getLogger(LoginController.class);
 
@@ -17,10 +20,12 @@ public void doPost(HttpRequest request, HttpResponse response) {
         User targetUser = DataBase.findUserById(userId);
         // todo : 세션의 작동원리를 깊히 생각해보기
         if (targetUser == null || !password.equals(targetUser.getPassword())) {
-            response.addHeader("Set-Cookie", "logined=false");
+            response.addHeader("Set-Cookie", "loggedIn=false");
             response.sendRedirect("/user/login_failed.html");
         } else if (password.equals(targetUser.getPassword())) {
-            response.addHeader("Set-Cookie", "logined=true");
+            UUID uuid = UUID.randomUUID();
+            SessionDataBase.sessions.put(uuid.toString(), targetUser);
+            response.addHeader("Set-Cookie", SessionDataBase.JSESSIONID + "=" + uuid);
             response.sendRedirect("/index.html");
             log.info("{}님이 로그인하셨습니다.", userId);
         }

src/main/java/db/SessionDataBase.java

@@ -0,0 +1,20 @@
+package db;
+
+import com.google.common.collect.Maps;
+import model.User;
+
+import java.util.Map;
+
+public class SessionDataBase {
+    public static Map<String, User> sessions = Maps.newHashMap();
+
+    public static final String JSESSIONID = "JSESSIONID";
+
+    public static boolean isLoginUser(String sessionId) {
+        return getSessionUser(sessionId) != null;
+    }
+
+    public static User getSessionUser(String sessionId) {
+        return sessions.get(sessionId);
+    }
+}

src/main/java/webserver/HttpResponse.java

@@ -5,6 +5,7 @@
 
 import java.io.DataOutputStream;
 import java.io.*;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.util.HashMap;
 import java.util.Map;
@@ -37,6 +38,12 @@ public void forward(String url) throws IOException {
         responseBody(body);
     }
 
+    public void forwardBody(String result) {
+        byte[] body = result.getBytes(StandardCharsets.UTF_8);
+        response200Header(body.length, "text/html");
+        responseBody(body);
+    }
+
     public void response200Header(int lengthOfBodyContent, String contentType) {
         try {
             dos.writeBytes("HTTP/1.1 200 OK \r\n");