refactor: DispatcherServlet에서 JspView 의존성 제거

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

@@ -1,10 +1,17 @@
 package com.techcourse;
 
+import com.techcourse.exception.NotFoundExceptionHandler;
 import jakarta.servlet.ServletContext;
+import java.util.List;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import web.org.springframework.web.WebApplicationInitializer;
 import webmvc.org.springframework.web.servlet.DispatcherServlet;
+import webmvc.org.springframework.web.servlet.mvc.tobe.adapter.AnnotationHandlerAdapter;
+import webmvc.org.springframework.web.servlet.mvc.tobe.adapter.HandlerAdapterFinder;
+import webmvc.org.springframework.web.servlet.mvc.tobe.exception.ExceptionResolver;
+import webmvc.org.springframework.web.servlet.mvc.tobe.handler.AnnotationHandlerMapping;
+import webmvc.org.springframework.web.servlet.mvc.tobe.handler.HandlerMapping;
 
 /**
  * Base class for {@link WebApplicationInitializer}
@@ -18,7 +25,7 @@ public class DispatcherServletInitializer implements WebApplicationInitializer {
 
  @Override
  public void onStartup(final ServletContext servletContext) {
- final var dispatcherServlet = new DispatcherServlet();
+ final var dispatcherServlet = initDispatcherServlet();
 
  final var registration = servletContext.addServlet(DEFAULT_SERVLET_NAME, dispatcherServlet);
  if (registration == null) {
@@ -31,4 +38,12 @@ public void onStartup(final ServletContext servletContext) {
 
  log.info("Start AppWebApplication Initializer");
  }
+
+ public DispatcherServlet initDispatcherServlet() {
+ HandlerMapping handlerMapping = new AnnotationHandlerMapping();
+ handlerMapping.initialize();
+ HandlerAdapterFinder handlerAdapterFinder = new HandlerAdapterFinder(List.of(new AnnotationHandlerAdapter()));
+ ExceptionResolver exceptionResolver = new ExceptionResolver(List.of(new NotFoundExceptionHandler()));
+ return new DispatcherServlet(handlerMapping, handlerAdapterFinder, exceptionResolver);
+ }
 }

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

@@ -1,14 +1,14 @@
 package com.techcourse;
 
+import com.techcourse.exception.UncheckedServletException;
+import java.io.File;
 import org.apache.catalina.Context;
 import org.apache.catalina.LifecycleException;
 import org.apache.catalina.connector.Connector;
 import org.apache.catalina.core.StandardContext;
 import org.apache.catalina.startup.Tomcat;
 import org.apache.tomcat.util.scan.StandardJarScanner;
 
-import java.io.File;
-
 public class TomcatStarter {
 
  public static final String WEBAPP_DIR_LOCATION = "app/src/main/webapp/";

app/src/main/java/com/techcourse/exception/NotFoundExceptionHandler.java

@@ -0,0 +1,19 @@
+package com.techcourse.exception;
+
+import webmvc.org.springframework.web.servlet.ModelAndView;
+import webmvc.org.springframework.web.servlet.mvc.tobe.exception.HandlerNotFoundException;
+import webmvc.org.springframework.web.servlet.mvc.tobe.handler.ExceptionHandler;
+import webmvc.org.springframework.web.servlet.view.JspView;
+
+public class NotFoundExceptionHandler implements ExceptionHandler {
+
+ @Override
+ public boolean support(Throwable ex) {
+ return ex instanceof HandlerNotFoundException;
+ }
+
+ @Override
+ public ModelAndView handle() {
+ return new ModelAndView(new JspView("/404.jsp"));
+ }
+}

app/src/main/java/com/techcourse/UncheckedServletException.java → app/src/main/java/com/techcourse/exception/UncheckedServletException.java

@@ -1,4 +1,4 @@
-package com.techcourse;
+package com.techcourse.exception;
 
 public class UncheckedServletException extends RuntimeException {
 

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

@@ -4,44 +4,27 @@
 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.mvc.tobe.adapter.AnnotationHandlerAdapter;
 import webmvc.org.springframework.web.servlet.mvc.tobe.adapter.HandlerAdapter;
 import webmvc.org.springframework.web.servlet.mvc.tobe.adapter.HandlerAdapterFinder;
 import webmvc.org.springframework.web.servlet.mvc.tobe.exception.ExceptionResolver;
-import webmvc.org.springframework.web.servlet.mvc.tobe.handler.AnnotationHandlerMapping;
 import webmvc.org.springframework.web.servlet.mvc.tobe.handler.HandlerMapping;
 
 public class DispatcherServlet extends HttpServlet {
 
  private static final long serialVersionUID = 1L;
  private static final Logger log = LoggerFactory.getLogger(DispatcherServlet.class);
 
- private HandlerMapping handlerMapping;
- private HandlerAdapterFinder handlerAdapterFinder;
- private ExceptionResolver exceptionResolver;
+ private final HandlerMapping handlerMapping;
+ private final HandlerAdapterFinder handlerAdapterFinder;
+ private final ExceptionResolver exceptionResolver;
 
- public DispatcherServlet() {
- }
-
- @Override
- public void init() {
- handlerMapping = initHandlerMappings();
- handlerAdapterFinder = initHandlerAdapterFinder();
- exceptionResolver = new ExceptionResolver();
- }
-
- private HandlerMapping initHandlerMappings() {
- HandlerMapping handlerMapping = new AnnotationHandlerMapping("com");
- handlerMapping.initialize();
- return handlerMapping;
- }
-
- private HandlerAdapterFinder initHandlerAdapterFinder() {
- return new HandlerAdapterFinder(
- List.of(new AnnotationHandlerAdapter()));
+ public DispatcherServlet(HandlerMapping handlerMapping, HandlerAdapterFinder handlerAdapterFinder,
+ ExceptionResolver exceptionResolver) {
+ this.handlerMapping = handlerMapping;
+ this.handlerAdapterFinder = handlerAdapterFinder;
+ this.exceptionResolver = exceptionResolver;
  }
 
  @Override

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

@@ -1,7 +1,7 @@
 package webmvc.org.springframework.web.servlet.mvc.tobe.adapter;
 
-import com.sun.jdi.InternalException;
 import java.util.List;
+import webmvc.org.springframework.web.servlet.mvc.tobe.exception.HandlerNotFoundException;
 
 public class HandlerAdapterFinder {
 
@@ -15,6 +15,6 @@ public HandlerAdapter find(Object handler) {
  return handlerAdapters.stream()
  .filter(it -> it.supports(handler))
  .findFirst()
- .orElseThrow(InternalException::new);
+ .orElseThrow(HandlerNotFoundException::new);
  }
 }

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

@@ -1,21 +1,24 @@
 package webmvc.org.springframework.web.servlet.mvc.tobe.exception;
 
+import com.sun.jdi.InternalException;
+import java.util.List;
 import webmvc.org.springframework.web.servlet.ModelAndView;
-import webmvc.org.springframework.web.servlet.view.JspView;
+import webmvc.org.springframework.web.servlet.mvc.tobe.handler.ExceptionHandler;
 
 public class ExceptionResolver {
 
- public ModelAndView handle(Throwable ex) {
- ModelAndView mv = null;
- if (ex instanceof HandlerNotFoundException) {
- mv = new ModelAndView(new JspView("/404.jsp"));
- }
+ private final List<ExceptionHandler> handlers;
 
-  if (mv == null) {
-  return new ModelAndView(new JspView("/500.jsp"));
-  }
+ public ExceptionResolver(List<ExceptionHandler> handlers) {
+ this.handlers = handlers;
+ }
 
- return mv;
+ public ModelAndView handle(Throwable ex) {
+ ExceptionHandler handler = handlers.stream()
+ .filter(it -> it.support(ex))
+ .findFirst()
+ .orElseThrow(() -> new InternalException());
+ return handler.handle();
  }
 }
 

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

@@ -0,0 +1,10 @@
+package webmvc.org.springframework.web.servlet.mvc.tobe.handler;
+
+import webmvc.org.springframework.web.servlet.ModelAndView;
+
+public interface ExceptionHandler {
+
+ boolean support(Throwable ex);
+
+ ModelAndView handle();
+}