[MVC 구현하기 - 1단계] 에버(손채영) 미션 제출합니다.

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

@@ -1,12 +1,14 @@
 package com.techcourse;
 
+import com.interface21.webmvc.servlet.ModelAndView;
+import com.interface21.webmvc.servlet.View;
+import com.interface21.webmvc.servlet.view.JspView;
 import jakarta.servlet.ServletException;
 import jakarta.servlet.http.HttpServlet;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import com.interface21.webmvc.servlet.view.JspView;
 
 public class DispatcherServlet extends HttpServlet {
 
@@ -25,27 +27,20 @@ public void init() {
     }
 
     @Override
-    protected void service(final HttpServletRequest request, final HttpServletResponse response) throws ServletException {
+    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);
+            ModelAndView modelAndView = new ModelAndView(new JspView(viewName));
+            View view = modelAndView.getView();
+            view.render(modelAndView.getModel(), request, response);
         } catch (Throwable e) {
             log.error("Exception : {}", e.getMessage(), e);
             throw new ServletException(e.getMessage());
         }
     }
-
-    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);
-    }
 }

mvc/src/main/java/com/interface21/web/bind/annotation/RequestMethod.java

@@ -1,5 +1,14 @@
 package com.interface21.web.bind.annotation;
 
+import java.util.Arrays;
+
 public enum RequestMethod {
-    GET, HEAD, POST, PUT, PATCH, DELETE, OPTIONS, TRACE
+    GET, HEAD, POST, PUT, PATCH, DELETE, OPTIONS, TRACE;
+
+    public static RequestMethod find(String raw) {
+        return Arrays.stream(values())
+                .filter(value -> value.name().equals(raw))
+                .findAny()
+                .orElseThrow(() -> new IllegalArgumentException(String.format("유효하지 않은 요청 메서드입니다: %s", raw)));
+    }
 }

mvc/src/main/java/com/interface21/webmvc/servlet/mvc/tobe/AnnotationHandlerMapping.java

@@ -1,16 +1,25 @@
 package com.interface21.webmvc.servlet.mvc.tobe;
 
+import com.interface21.context.stereotype.Controller;
+import com.interface21.web.bind.annotation.RequestMapping;
+import com.interface21.web.bind.annotation.RequestMethod;
 import jakarta.servlet.http.HttpServletRequest;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
+import java.lang.reflect.Method;
+import java.util.Arrays;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
+import java.util.Set;
+import org.reflections.Reflections;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class AnnotationHandlerMapping {
 
     private static final Logger log = LoggerFactory.getLogger(AnnotationHandlerMapping.class);
 
+    private static final int EMPTY_REQUEST_METHODS = 0;
+
     private final Object[] basePackage;
     private final Map<HandlerKey, HandlerExecution> handlerExecutions;
 
@@ -21,9 +30,57 @@ public AnnotationHandlerMapping(final Object... basePackage) {
 
     public void initialize() {
         log.info("Initialized AnnotationHandlerMapping!");
+        Reflections reflections = new Reflections(basePackage);
+        Set<Class<?>> controllerTypes = reflections.getTypesAnnotatedWith(Controller.class);
+        controllerTypes.forEach(this::mapControllerHandlers);
+    }
+
+    private void mapControllerHandlers(Class<?> controllerType) {
+        try {
+            Object controller = controllerType.getConstructor().newInstance();
+            Method[] handlers = controllerType.getDeclaredMethods();
+            mapHandlerToExecution(controller, handlers);
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private void mapHandlerToExecution(Object controller, Method[] handlers) {
+        Arrays.stream(handlers)
+                .filter(handler -> handler.isAnnotationPresent(RequestMapping.class))
+                .forEach(handler -> addMapper(handler, new HandlerExecution(controller, handler)));
+    }
+
+    private void addMapper(Method handler, HandlerExecution handlerExecution) {
+        RequestMapping requestMapping = handler.getAnnotation(RequestMapping.class);
+        List<HandlerKey> handlerKeys = createHandlerKeys(requestMapping);
+        handlerKeys.forEach(handlerKey -> handlerExecutions.put(handlerKey, handlerExecution));
+    }
+
+    private List<HandlerKey> createHandlerKeys(RequestMapping requestMapping) {
+        String uri = requestMapping.value();
+        RequestMethod[] requestMethods = requestMapping.method();
+        if (requestMethods.length == EMPTY_REQUEST_METHODS) {
+            requestMethods = RequestMethod.values();
+        }
+        return Arrays.stream(requestMethods)
+                .map(requestMethod -> HandlerKey.from(uri, requestMethod))
+                .toList();
     }
 
     public Object getHandler(final HttpServletRequest request) {
-        return null;
+        HandlerKey handlerKey = createHandlerKey(request);
+        HandlerExecution handlerExecution = handlerExecutions.get(handlerKey);
+        if (handlerExecution == null) {
+            throw new IllegalArgumentException(
+                    String.format("해당 요청에 대응하는 핸들러가 없습니다: %s %s", request.getMethod(), request.getRequestURI()));
+        }
+        return handlerExecution;
+    }
+
+    private HandlerKey createHandlerKey(HttpServletRequest request) {
+        String requestURI = request.getRequestURI();
+        RequestMethod requestMethod = RequestMethod.find(request.getMethod());
+        return HandlerKey.from(requestURI, requestMethod);
     }
 }

mvc/src/main/java/com/interface21/webmvc/servlet/mvc/tobe/HandlerExecution.java

@@ -1,12 +1,26 @@
 package com.interface21.webmvc.servlet.mvc.tobe;
 
+import com.interface21.webmvc.servlet.ModelAndView;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
-import com.interface21.webmvc.servlet.ModelAndView;
+import java.lang.reflect.Method;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class HandlerExecution {
 
+    private static final Logger log = LoggerFactory.getLogger(HandlerExecution.class);
+
+    private final Object controller;
+    private final Method handler;
+
+    public HandlerExecution(Object controller, Method handler) {
+        this.controller = controller;
+        this.handler = handler;
+    }
+
     public ModelAndView handle(final HttpServletRequest request, final HttpServletResponse response) throws Exception {
-        return null;
+        log.info("handler execution handle");
+        return (ModelAndView) handler.invoke(controller, request, response);
     }
 }

mvc/src/main/java/com/interface21/webmvc/servlet/mvc/tobe/HandlerKey.java

@@ -1,37 +1,53 @@
 package com.interface21.webmvc.servlet.mvc.tobe;
 
 import com.interface21.web.bind.annotation.RequestMethod;
-
+import java.util.Map;
 import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
 
 public class HandlerKey {
 
-    private final String url;
-    private final RequestMethod requestMethod;
+    private static final Map<String, HandlerKey> CACHE = new ConcurrentHashMap<>();
 
-    public HandlerKey(final String url, final RequestMethod requestMethod) {
-        this.url = url;
-        this.requestMethod = requestMethod;
+    public final String url;
+    public final RequestMethod requestMethod;
+
+    public static HandlerKey from(String url, RequestMethod requestMethod) {
+        String key = url + requestMethod.name();
+        if (CACHE.containsKey(key)) {
+            return CACHE.get(key);
+        }
+        return new HandlerKey(url, requestMethod);
     }
 
-    @Override
-    public String toString() {
-        return "HandlerKey{" +
-                "url='" + url + '\'' +
-                ", requestMethod=" + requestMethod +
-                '}';
+    private HandlerKey(final String url, final RequestMethod requestMethod) {
+        this.url = url;
+        this.requestMethod = requestMethod;
+        CACHE.put(url + requestMethod.name(), this);
     }
 
     @Override
     public boolean equals(Object o) {
-        if (this == o) return true;
-        if (!(o instanceof HandlerKey)) return false;
-        HandlerKey that = (HandlerKey) o;
-        return Objects.equals(url, that.url) && requestMethod == that.requestMethod;
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof HandlerKey)) {
+            return false;
+        }
+        HandlerKey handlerKey = (HandlerKey) o;
+        return Objects.equals(url, handlerKey.url) && requestMethod == handlerKey.requestMethod;
     }
 
     @Override
     public int hashCode() {
         return Objects.hash(url, requestMethod);
     }
+
+    @Override
+    public String toString() {
+        return "HandlerKey{" +
+                "url='" + url + '\'' +
+                ", requestMethod=" + requestMethod +
+                '}';
+    }
 }

mvc/src/main/java/com/interface21/webmvc/servlet/view/JspView.java

@@ -1,6 +1,7 @@
 package com.interface21.webmvc.servlet.view;
 
 import com.interface21.webmvc.servlet.View;
+import jakarta.servlet.RequestDispatcher;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import org.slf4j.Logger;
@@ -14,18 +15,27 @@ public class JspView implements View {
 
     public static final String REDIRECT_PREFIX = "redirect:";
 
+    private final String viewName;
+
     public JspView(final String viewName) {
+        this.viewName = viewName;
     }
 
     @Override
     public void render(final Map<String, ?> model, final HttpServletRequest request, final HttpServletResponse response) throws Exception {
-        // todo
+        log.info("jsp view render");
 
         model.keySet().forEach(key -> {
             log.debug("attribute name : {}, value : {}", key, model.get(key));
             request.setAttribute(key, model.get(key));
         });
 
-        // todo
+        if (viewName.startsWith(REDIRECT_PREFIX)) {
+            response.sendRedirect(viewName.substring(REDIRECT_PREFIX.length()));
+            return;
+        }
+
+        RequestDispatcher requestDispatcher = request.getRequestDispatcher(viewName);
+        requestDispatcher.forward(request, response);
     }
 }

mvc/src/test/java/com/interface21/web/bind/annotation/RequestMethodTest.java

@@ -0,0 +1,35 @@
+package com.interface21.web.bind.annotation;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+class RequestMethodTest {
+
+    @DisplayName("전달받은 문자열과 형태가 같은 요청 메서드를 반환한다.")
+    @Test
+    void should_findRequestMethod_when_givenValidString() {
+        // given
+        String raw = "GET";
+
+        // when
+        RequestMethod requestMethod = RequestMethod.find(raw);
+
+        // then
+        assertThat(requestMethod).isEqualTo(RequestMethod.GET);
+    }
+
+    @DisplayName("전달받은 문자열이 유효하지 않은 경우 예외가 발생한다.")
+    @Test
+    void should_throwException_when_givenInvalidString() {
+        // given
+        String raw = "INVALID";
+
+        // when & then
+        assertThatThrownBy(() -> RequestMethod.find(raw))
+                .isInstanceOf(IllegalArgumentException.class)
+                .hasMessage("유효하지 않은 요청 메서드입니다: " + raw);
+    }
+}