[MVC 구현하기 - 2단계] 우르(김현우) 미션 제출합니다.

app/src/main/java/com/techcourse/DispatcherServlet.java

@@ -4,48 +4,90 @@
 import jakarta.servlet.http.HttpServlet;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
+import java.util.List;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import webmvc.org.springframework.web.servlet.ModelAndView;
+import webmvc.org.springframework.web.servlet.mvc.tobe.AnnotationHandlerAdapter;
+import webmvc.org.springframework.web.servlet.mvc.tobe.AnnotationHandlerMapping;
+import webmvc.org.springframework.web.servlet.mvc.tobe.HandlerAdapter;
+import webmvc.org.springframework.web.servlet.mvc.tobe.HandlerAdapters;
+import webmvc.org.springframework.web.servlet.mvc.tobe.HandlerMapping;
+import webmvc.org.springframework.web.servlet.mvc.tobe.HandlerMappings;
+import webmvc.org.springframework.web.servlet.mvc.tobe.ManualHandlerAdapter;
 import webmvc.org.springframework.web.servlet.view.JspView;
 
 public class DispatcherServlet extends HttpServlet {
 
-    private static final long serialVersionUID = 1L;
-    private static final Logger log = LoggerFactory.getLogger(DispatcherServlet.class);
+  private static final long serialVersionUID = 1L;
+  private static final Logger log = LoggerFactory.getLogger(DispatcherServlet.class);
 
-    private ManualHandlerMapping manualHandlerMapping;
+  private HandlerMapping handlerMappingComposite;
+  private HandlerAdapter handlerAdapterComposite;
 
-    public DispatcherServlet() {
-    }
+  public DispatcherServlet() {
+  }
+
+  @Override
+  public void init() {
+    handlerMappingComposite = new HandlerMappings(
+        List.of(
+            new ManualHandlerMapping(),
+            new AnnotationHandlerMapping("com.techcourse")
+        )
+    );
+
+    handlerAdapterComposite = new HandlerAdapters(
+        List.of(
+            new ManualHandlerAdapter(),
+            new AnnotationHandlerAdapter()
+        )
+    );
+  }
+
+  @Override
+  protected void service(final HttpServletRequest request, final HttpServletResponse response)
+      throws ServletException {
+    final String requestURI = request.getRequestURI();
+    log.debug("Method : {}, Request URI : {}", request.getMethod(), requestURI);
 
-    @Override
-    public void init() {
-        manualHandlerMapping = new ManualHandlerMapping();
-        manualHandlerMapping.initialize();
+    try {
+      final Object handler = handlerMappingComposite.getHandler(request);
+      final Object handleValue = handlerAdapterComposite.handle(request, response, handler);
+
+      // TODO : 3단계 리팩터링
+      renderByHandlerValueType(request, response, handleValue);
+
+    } catch (Throwable e) {
+      log.error("Exception : {}", e.getMessage(), e);
+      throw new ServletException(e.getMessage());
     }
+  }
 
-    @Override
-    protected void service(final HttpServletRequest request, final HttpServletResponse response) throws ServletException {
-        final String requestURI = request.getRequestURI();
-        log.debug("Method : {}, Request URI : {}", request.getMethod(), requestURI);
-
-        try {
-            final var controller = manualHandlerMapping.getHandler(requestURI);
-            final var viewName = controller.execute(request, response);
-            move(viewName, request, response);
-        } catch (Throwable e) {
-            log.error("Exception : {}", e.getMessage(), e);
-            throw new ServletException(e.getMessage());
-        }
+  private void renderByHandlerValueType(
+      final HttpServletRequest request,
+      final HttpServletResponse response,
+      final Object handleValue
+  ) throws Exception {
+    if (handleValue instanceof ModelAndView) {
+      final ModelAndView modelAndView = (ModelAndView) handleValue;
+      move(modelAndView.getView().getName(), request, response);
     }
 
-    private void move(final String viewName, final HttpServletRequest request, final HttpServletResponse response) throws Exception {
-        if (viewName.startsWith(JspView.REDIRECT_PREFIX)) {
-            response.sendRedirect(viewName.substring(JspView.REDIRECT_PREFIX.length()));
-            return;
-        }
+    if (handleValue instanceof String) {
+      final String viewName = (String) handleValue;
+      move(viewName, request, response);
+    }
+  }
 
-        final var requestDispatcher = request.getRequestDispatcher(viewName);
-        requestDispatcher.forward(request, response);
+  private void move(final String viewName, final HttpServletRequest request,
+      final HttpServletResponse response) throws Exception {
+    if (viewName.startsWith(JspView.REDIRECT_PREFIX)) {
+      response.sendRedirect(viewName.substring(JspView.REDIRECT_PREFIX.length()));
+      return;
     }
+
+    final var requestDispatcher = request.getRequestDispatcher(viewName);
+    requestDispatcher.forward(request, response);
+  }
 }

app/src/main/java/com/techcourse/ManualHandlerMapping.java

@@ -1,34 +1,37 @@
 package com.techcourse;
 
 import com.techcourse.controller.*;
+import jakarta.servlet.http.HttpServletRequest;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import webmvc.org.springframework.web.servlet.mvc.asis.Controller;
 import webmvc.org.springframework.web.servlet.mvc.asis.ForwardController;
 
 import java.util.HashMap;
 import java.util.Map;
+import webmvc.org.springframework.web.servlet.mvc.tobe.HandlerMapping;
 
-public class ManualHandlerMapping {
+public class ManualHandlerMapping implements HandlerMapping {
 
     private static final Logger log = LoggerFactory.getLogger(ManualHandlerMapping.class);
 
     private static final Map<String, Controller> controllers = new HashMap<>();
 
+    @Override
     public void initialize() {
         controllers.put("/", new ForwardController("/index.jsp"));
         controllers.put("/login", new LoginController());
         controllers.put("/login/view", new LoginViewController());
         controllers.put("/logout", new LogoutController());
-        controllers.put("/register/view", new RegisterViewController());
-        controllers.put("/register", new RegisterController());
 
         log.info("Initialized Handler Mapping!");
         controllers.keySet()
                 .forEach(path -> log.info("Path : {}, Controller : {}", path, controllers.get(path).getClass()));
     }
 
-    public Controller getHandler(final String requestURI) {
+    @Override
+    public Object getHandler(final HttpServletRequest httpServletRequest) {
+        final String requestURI = httpServletRequest.getRequestURI();
         log.debug("Request Mapping Uri : {}", requestURI);
         return controllers.get(requestURI);
     }

app/src/main/java/com/techcourse/controller/RegisterController.java

@@ -2,20 +2,26 @@
 
 import com.techcourse.domain.User;
 import com.techcourse.repository.InMemoryUserRepository;
+import context.org.springframework.stereotype.Controller;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
-import webmvc.org.springframework.web.servlet.mvc.asis.Controller;
+import web.org.springframework.web.bind.annotation.RequestMapping;
+import web.org.springframework.web.bind.annotation.RequestMethod;
+import webmvc.org.springframework.web.servlet.ModelAndView;
+import webmvc.org.springframework.web.servlet.view.JspView;
 
-public class RegisterController implements Controller {
+@Controller
+public class RegisterController {
 
-    @Override
-    public String execute(final HttpServletRequest req, final HttpServletResponse res) throws Exception {
+    @RequestMapping(value = "/register", method = RequestMethod.POST)
+    public ModelAndView execute(final HttpServletRequest req, final HttpServletResponse res) throws Exception {
         final var user = new User(2,
                 req.getParameter("account"),
                 req.getParameter("password"),
                 req.getParameter("email"));
         InMemoryUserRepository.save(user);
 
-        return "redirect:/index.jsp";
+        final ModelAndView modelAndView = new ModelAndView(new JspView("redirect:/index.jsp"));
+        return modelAndView;
     }
 }

app/src/main/java/com/techcourse/controller/RegisterViewController.java

@@ -1,13 +1,24 @@
 package com.techcourse.controller;
 
+import context.org.springframework.stereotype.Controller;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
-import webmvc.org.springframework.web.servlet.mvc.asis.Controller;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import web.org.springframework.web.bind.annotation.RequestMapping;
+import web.org.springframework.web.bind.annotation.RequestMethod;
+import webmvc.org.springframework.web.servlet.ModelAndView;
+import webmvc.org.springframework.web.servlet.view.JspView;
 
-public class RegisterViewController implements Controller {
+@Controller
+public class RegisterViewController {
 
-    @Override
-    public String execute(final HttpServletRequest req, final HttpServletResponse res) throws Exception {
-        return "/register.jsp";
+    private static final Logger log = LoggerFactory.getLogger(RegisterViewController.class);
+
+    @RequestMapping(value = "/register", method = RequestMethod.GET)
+    public ModelAndView execute(final HttpServletRequest req, final HttpServletResponse res) {
+        log.info("RegisterViewController GET method");
+
+        return new ModelAndView(new JspView("/register.jsp"));
     }
 }

mvc/src/main/java/web/org/springframework/web/bind/annotation/RequestMethod.java

@@ -1,7 +1,5 @@
 package web.org.springframework.web.bind.annotation;
 
-import java.util.Arrays;
-
 public enum RequestMethod {
   GET,
   HEAD,
@@ -12,11 +10,4 @@ public enum RequestMethod {
   OPTIONS,
   TRACE
   ;
-
-  public static RequestMethod find(final String method) {
-    return Arrays.stream(values())
-        .filter(it -> it.name().equals(method.toUpperCase()))
-        .findAny()
-        .orElseThrow(() -> new IllegalArgumentException("지원하지 않는 RequestMethod입니다."));
-  }
 }

mvc/src/main/java/webmvc/org/springframework/web/servlet/View.java

@@ -7,4 +7,6 @@
 
 public interface View {
     void render(Map<String, ?> model, HttpServletRequest request, HttpServletResponse response) throws Exception;
+
+    String getName();
 }

mvc/src/main/java/webmvc/org/springframework/web/servlet/mvc/tobe/AnnotationHandlerAdapter.java

@@ -0,0 +1,21 @@
+package webmvc.org.springframework.web.servlet.mvc.tobe;
+
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+public class AnnotationHandlerAdapter implements HandlerAdapter {
+
+  @Override
+  public boolean isSupport(final Object handler) {
+    return handler instanceof HandlerExecution;
+  }
+
+  @Override
+  public Object handle(
+      final HttpServletRequest request,
+      final HttpServletResponse response,
+      final Object handler
+  ) {
+    return ((HandlerExecution) handler).handle(request, response);
+  }
+}

mvc/src/main/java/webmvc/org/springframework/web/servlet/mvc/tobe/AnnotationHandlerMapping.java

@@ -14,7 +14,7 @@
 import web.org.springframework.web.bind.annotation.RequestMapping;
 import web.org.springframework.web.bind.annotation.RequestMethod;
 
-public class AnnotationHandlerMapping {
+public class AnnotationHandlerMapping implements HandlerMapping {
 
   private static final Logger log = LoggerFactory.getLogger(AnnotationHandlerMapping.class);
 
@@ -26,23 +26,41 @@ public AnnotationHandlerMapping(final Object... basePackages) {
     this.handlerExecutions = new HashMap<>();
   }
 
-  public void initialize()
-      throws NoSuchMethodException, InvocationTargetException, InstantiationException, IllegalAccessException {
-    log.info("Initialized AnnotationHandlerMapping!");
-
+  @Override
+  public void initialize() {
     final Reflections reflections = new Reflections(basePackages);
 
     final Set<Class<?>> controllerAnnotationClasses =
         reflections.getTypesAnnotatedWith(Controller.class);
 
     for (Class<?> controllerAnnotationClass : controllerAnnotationClasses) {
-      final Object instance = controllerAnnotationClass.getDeclaredConstructor().newInstance();
+      final Object instance = getControllerInstance(controllerAnnotationClass);
       final Method[] methods = controllerAnnotationClass.getDeclaredMethods();
 
       Arrays.stream(methods)
           .filter(method -> method.isAnnotationPresent(RequestMapping.class))
           .forEach(method -> putHandlerExecutions(method, instance));
     }
+
+    log.info("Initialized AnnotationHandlerMapping!");
+
+    handlerExecutions.keySet()
+        .forEach(handlerKey -> log.info("handlerKey : {}, Controller : {}", handlerKey,
+            handlerExecutions.get(handlerKey)));
+  }
+
+  private Object getControllerInstance(final Class<?> controllerAnnotationClass) {
+    final Object instance;
+    try {
+      instance = controllerAnnotationClass.getDeclaredConstructor().newInstance();
+    } catch (InstantiationException
+             | IllegalAccessException
+             | InvocationTargetException
+             | NoSuchMethodException e
+    ) {
+      throw new IllegalArgumentException("AnnotationHandlerMapping Reflection Exception");
+    }
+    return instance;
   }
 
   private void putHandlerExecutions(final Method method, final Object target) {
@@ -55,11 +73,12 @@ private void putHandlerExecutions(final Method method, final Object target) {
     }
   }
 
+  @Override
   public Object getHandler(final HttpServletRequest request) {
     final String requestURI = request.getRequestURI();
     final String method = request.getMethod();
 
-    final HandlerKey handlerKey = new HandlerKey(requestURI, RequestMethod.find(method));
+    final HandlerKey handlerKey = new HandlerKey(requestURI, RequestMethod.valueOf(method));
 
     return handlerExecutions.get(handlerKey);
   }

mvc/src/main/java/webmvc/org/springframework/web/servlet/mvc/tobe/HandlerAdapter.java

@@ -0,0 +1,15 @@
+package webmvc.org.springframework.web.servlet.mvc.tobe;
+
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+public interface HandlerAdapter {
+
+  boolean isSupport(final Object handler);
+
+  Object handle(
+      final HttpServletRequest request,
+      final HttpServletResponse response,
+      final Object handler
+  );
+}

mvc/src/main/java/webmvc/org/springframework/web/servlet/mvc/tobe/HandlerAdapters.java

@@ -0,0 +1,32 @@
+package webmvc.org.springframework.web.servlet.mvc.tobe;
+
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import java.util.List;
+
+public class HandlerAdapters implements HandlerAdapter {
+
+  private final List<HandlerAdapter> handlerAdapters;
+
+  public HandlerAdapters(final List<HandlerAdapter> handlerAdapters) {
+    this.handlerAdapters = handlerAdapters;
+  }
+
+  @Override
+  public boolean isSupport(final Object handler) {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public Object handle(
+      final HttpServletRequest request,
+      final HttpServletResponse response,
+      final Object handler
+  ) {
+    return handlerAdapters.stream()
+        .filter(handlerAdapter -> handlerAdapter.isSupport(handler))
+        .map(handlerAdapter -> handlerAdapter.handle(request, response, handler))
+        .findAny()
+        .orElseThrow(() -> new IllegalArgumentException("해당 요청은 처리할 수 없습니다."));
+  }
+}