[MVC 구현하기 - 1단계] 무민(박무현) 미션 제출합니다.

README.md

@@ -1 +1,6 @@
 # @MVC 구현하기
+
+---
+
+## 1. @MVC 프레임워크 구현하기
+- [x] AnnotationHandlerMapping 구현  

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

@@ -1,11 +1,20 @@
 package webmvc.org.springframework.web.servlet.mvc.tobe;
 
+import context.org.springframework.stereotype.Controller;
 import jakarta.servlet.http.HttpServletRequest;
+import org.reflections.Reflections;
 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 java.lang.reflect.Method;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 public class AnnotationHandlerMapping {
 
@@ -21,9 +30,43 @@ public AnnotationHandlerMapping(final Object... basePackage) {
 
     public void initialize() {
         log.info("Initialized AnnotationHandlerMapping!");
+        Reflections reflections = new Reflections(basePackage);
+        Set<Class<?>> controllers = reflections.getTypesAnnotatedWith(Controller.class);
+        List<Method> requestMappingMethods = mapRequestMappingMethods(controllers);
+
+        putHandlerExecutions(requestMappingMethods);
+    }
+
+    private List<Method> mapRequestMappingMethods(Set<Class<?>> controllers) {
+        return controllers.stream()
+                .map(Class::getDeclaredMethods).flatMap(Stream::of)
+                .filter(method -> method.isAnnotationPresent(RequestMapping.class))
+                .collect(Collectors.toList());
+    }
+
+    private void putHandlerExecutions(List<Method> requestMappingMethods) {
+        requestMappingMethods.forEach(method -> {
+            Object controller = createControllerInstance(method);
+            RequestMapping annotation = method.getAnnotation(RequestMapping.class);
+            String path = annotation.value();
+            RequestMethod[] requestMethods = annotation.method();
+            RequestMethod requestMethod = RequestMethod.valueOf(requestMethods[0].name());
+            handlerExecutions.put(new HandlerKey(path, requestMethod), new HandlerExecution(controller, method));
+        });
+    }
+
+    private Object createControllerInstance(Method method) {
+        try {
+            return method.getDeclaringClass().newInstance();
+        } catch (InstantiationException | IllegalAccessException e) {
+            throw new IllegalArgumentException(e);
+        }
     }
 
     public Object getHandler(final HttpServletRequest request) {
-        return null;
+        RequestMethod requestMethod = RequestMethod.valueOf(request.getMethod());
+        HandlerKey handlerKey = new HandlerKey(request.getRequestURI(), requestMethod);
+
+        return handlerExecutions.get(handlerKey);
     }
 }

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

@@ -4,9 +4,19 @@
 import jakarta.servlet.http.HttpServletResponse;
 import webmvc.org.springframework.web.servlet.ModelAndView;
 
+import java.lang.reflect.Method;
+
 public class HandlerExecution {
 
+    private final Object controller;
+    private final Method method;
+
+    public HandlerExecution(Object controller, Method method) {
+        this.controller = controller;
+        this.method = method;
+    }
+
     public ModelAndView handle(final HttpServletRequest request, final HttpServletResponse response) throws Exception {
-        return null;
+        return (ModelAndView) method.invoke(controller, request, response);
     }
 }

study/src/main/java/servlet/com/example/CharacterEncodingFilter.java

@@ -11,6 +11,7 @@ public class CharacterEncodingFilter implements Filter {
     @Override
     public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
         request.getServletContext().log("doFilter() 호출");
+        response.setCharacterEncoding("UTF-8");
         chain.doFilter(request, response);
     }
 }

study/src/test/java/reflection/Junit3TestRunner.java

@@ -2,12 +2,23 @@
 
 import org.junit.jupiter.api.Test;
 
+import java.util.Arrays;
+
 class Junit3TestRunner {
 
     @Test
     void run() throws Exception {
         Class<Junit3Test> clazz = Junit3Test.class;
 
         // TODO Junit3Test에서 test로 시작하는 메소드 실행
+        Arrays.stream(clazz.getMethods())
+                .filter(c -> c.getName().startsWith("test"))
+                .forEach(c -> {
+                    try {
+                        c.invoke(clazz.newInstance());
+                    } catch (Exception e) {
+                        e.printStackTrace();
+                    }
+                });
     }
 }

study/src/test/java/reflection/Junit4TestRunner.java

@@ -2,12 +2,23 @@
 
 import org.junit.jupiter.api.Test;
 
+import java.util.Arrays;
+
 class Junit4TestRunner {
 
     @Test
     void run() throws Exception {
         Class<Junit4Test> clazz = Junit4Test.class;
 
         // TODO Junit4Test에서 @MyTest 애노테이션이 있는 메소드 실행
+        Arrays.stream(clazz.getMethods())
+                .filter(c -> c.isAnnotationPresent(MyTest.class))
+                .forEach(c -> {
+                    try {
+                        c.invoke(clazz.newInstance());
+                    } catch (Exception e) {
+                        e.printStackTrace();
+                    }
+                });
     }
 }

study/src/test/java/reflection/ReflectionTest.java

@@ -4,10 +4,13 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.lang.reflect.AccessibleObject;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
+import java.util.Arrays;
 import java.util.List;
+import java.util.stream.Collectors;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -18,35 +21,34 @@ class ReflectionTest {
     @Test
     void givenObject_whenGetsClassName_thenCorrect() {
         final Class<Question> clazz = Question.class;
-
-        assertThat(clazz.getSimpleName()).isEqualTo("");
-        assertThat(clazz.getName()).isEqualTo("");
-        assertThat(clazz.getCanonicalName()).isEqualTo("");
+        assertThat(clazz.getSimpleName()).isEqualTo("Question");
+        assertThat(clazz.getName()).isEqualTo("reflection.Question");
+        assertThat(clazz.getCanonicalName()).isEqualTo("reflection.Question");
     }
 
     @Test
     void givenClassName_whenCreatesObject_thenCorrect() throws ClassNotFoundException {
         final Class<?> clazz = Class.forName("reflection.Question");
 
-        assertThat(clazz.getSimpleName()).isEqualTo("");
-        assertThat(clazz.getName()).isEqualTo("");
-        assertThat(clazz.getCanonicalName()).isEqualTo("");
+        assertThat(clazz.getSimpleName()).isEqualTo("Question");
+        assertThat(clazz.getName()).isEqualTo("reflection.Question");
+        assertThat(clazz.getCanonicalName()).isEqualTo("reflection.Question");
     }
 
     @Test
     void givenObject_whenGetsFieldNamesAtRuntime_thenCorrect() {
         final Object student = new Student();
-        final Field[] fields = null;
-        final List<String> actualFieldNames = null;
+        final Field[] fields = student.getClass().getDeclaredFields();
+        final List<String> actualFieldNames = Arrays.stream(fields).map(Field::getName).collect(Collectors.toList());
 
         assertThat(actualFieldNames).contains("name", "age");
     }
 
     @Test
     void givenClass_whenGetsMethods_thenCorrect() {
         final Class<?> animalClass = Student.class;
-        final Method[] methods = null;
-        final List<String> actualMethods = null;
+        final Method[] methods = animalClass.getDeclaredMethods();
+        final List<String> actualMethods = Arrays.stream(methods).map(Method::getName).collect(Collectors.toList());
 
         assertThat(actualMethods)
                 .hasSize(3)
@@ -56,7 +58,7 @@ void givenClass_whenGetsMethods_thenCorrect() {
     @Test
     void givenClass_whenGetsAllConstructors_thenCorrect() {
         final Class<?> questionClass = Question.class;
-        final Constructor<?>[] constructors = null;
+        final Constructor<?>[] constructors = questionClass.getDeclaredConstructors();
 
         assertThat(constructors).hasSize(2);
     }
@@ -65,11 +67,11 @@ void givenClass_whenGetsAllConstructors_thenCorrect() {
     void givenClass_whenInstantiatesObjectsAtRuntime_thenCorrect() throws Exception {
         final Class<?> questionClass = Question.class;
 
-        final Constructor<?> firstConstructor = null;
-        final Constructor<?> secondConstructor = null;
+        final Constructor<?> firstConstructor = questionClass.getConstructor(String.class, String.class, String.class);
+        final Constructor<?> secondConstructor = questionClass.getConstructor(String.class, String.class, String.class);
 
-        final Question firstQuestion = null;
-        final Question secondQuestion = null;
+        final Question firstQuestion = (Question) firstConstructor.newInstance("gugu", "제목1", "내용1");
+        final Question secondQuestion = (Question) secondConstructor.newInstance("gugu", "제목2", "내용2");
 
         assertThat(firstQuestion.getWriter()).isEqualTo("gugu");
         assertThat(firstQuestion.getTitle()).isEqualTo("제목1");
@@ -82,15 +84,17 @@ void givenClass_whenInstantiatesObjectsAtRuntime_thenCorrect() throws Exception
     @Test
     void givenClass_whenGetsPublicFields_thenCorrect() {
         final Class<?> questionClass = Question.class;
-        final Field[] fields = null;
+        final Field[] fields = Arrays.stream(questionClass.getDeclaredFields())
+                .filter(AccessibleObject::isAccessible)
+                .toArray(Field[]::new);
 
         assertThat(fields).hasSize(0);
     }
 
     @Test
     void givenClass_whenGetsDeclaredFields_thenCorrect() {
         final Class<?> questionClass = Question.class;
-        final Field[] fields = null;
+        final Field[] fields = questionClass.getDeclaredFields();
 
         assertThat(fields).hasSize(6);
         assertThat(fields[0].getName()).isEqualTo("questionId");
@@ -99,31 +103,32 @@ void givenClass_whenGetsDeclaredFields_thenCorrect() {
     @Test
     void givenClass_whenGetsFieldsByName_thenCorrect() throws Exception {
         final Class<?> questionClass = Question.class;
-        final Field field = null;
+        final Field field = questionClass.getDeclaredField("questionId");
 
         assertThat(field.getName()).isEqualTo("questionId");
     }
 
     @Test
     void givenClassField_whenGetsType_thenCorrect() throws Exception {
         final Field field = Question.class.getDeclaredField("questionId");
-        final Class<?> fieldClass = null;
+        final Class<?> fieldClass = field.getType();
 
         assertThat(fieldClass.getSimpleName()).isEqualTo("long");
     }
 
     @Test
     void givenClassField_whenSetsAndGetsValue_thenCorrect() throws Exception {
         final Class<?> studentClass = Student.class;
-        final Student student = null;
-        final Field field = null;
+        final Student student = new Student();
+        final Field field = studentClass.getDeclaredField("age");
 
         // todo field에 접근 할 수 있도록 만든다.
+        field.setAccessible(true);
 
         assertThat(field.getInt(student)).isZero();
         assertThat(student.getAge()).isZero();
 
-        field.set(null, null);
+        field.set(student, 99);
 
         assertThat(field.getInt(student)).isEqualTo(99);
         assertThat(student.getAge()).isEqualTo(99);

study/src/test/java/reflection/ReflectionsTest.java

@@ -4,6 +4,9 @@
 import org.reflections.Reflections;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import reflection.annotation.Controller;
+import reflection.annotation.Repository;
+import reflection.annotation.Service;
 
 class ReflectionsTest {
 
@@ -14,5 +17,11 @@ void showAnnotationClass() throws Exception {
         Reflections reflections = new Reflections("reflection.examples");
 
         // TODO 클래스 레벨에 @Controller, @Service, @Repository 애노테이션이 설정되어 모든 클래스 찾아 로그로 출력한다.
+        reflections.getTypesAnnotatedWith(Controller.class)
+                .forEach(c -> log.info("{}", c.getSimpleName()));
+        reflections.getTypesAnnotatedWith(Service.class)
+                .forEach(c -> log.info("{}", c.getSimpleName()));
+        reflections.getTypesAnnotatedWith(Repository.class)
+                .forEach(c -> log.info("{}", c.getSimpleName()));
     }
 }

study/src/test/java/servlet/com/example/ServletTest.java

@@ -28,7 +28,7 @@ void testSharedCounter() {
 
         // expected를 0이 아닌 올바른 값으로 바꿔보자.
         // 예상한 결과가 나왔는가? 왜 이런 결과가 나왔을까?
-        assertThat(Integer.parseInt(response.body())).isEqualTo(0);
+        assertThat(Integer.parseInt(response.body())).isEqualTo(3);
     }
 
     @Test
@@ -50,6 +50,6 @@ void testLocalCounter() {
 
         // expected를 0이 아닌 올바른 값으로 바꿔보자.
         // 예상한 결과가 나왔는가? 왜 이런 결과가 나왔을까?
-        assertThat(Integer.parseInt(response.body())).isEqualTo(0);
+        assertThat(Integer.parseInt(response.body())).isEqualTo(1);
     }
 }