BAEL-325: Added intercepting filters.

patterns/pom.xml

@@ -4,7 +4,13 @@
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
 
-    <groupId>com.baeldung.enterprise.patterns</groupId>
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <groupId>com.baeldung.patterns</groupId>
     <artifactId>patterns</artifactId>
     <packaging>war</packaging>
 
@@ -15,14 +21,14 @@
             <version>3.1.0</version>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-api</artifactId>
+            <version>1.7.21</version>
+            <scope>provided</scope>
+        </dependency>
     </dependencies>
 
-    <parent>
-        <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
-    </parent>
-
     <build>
         <plugins>
             <plugin>
@@ -34,13 +40,21 @@
                     <target>1.8</target>
                 </configuration>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-war-plugin</artifactId>
+                <version>3.0.0</version>
+                <configuration>
+                    <failOnMissingWebXml>false</failOnMissingWebXml>
+                </configuration>
+            </plugin>
             <plugin>
                 <groupId>org.eclipse.jetty</groupId>
                 <artifactId>jetty-maven-plugin</artifactId>
-                <version>9.4.0.M1</version>
+                <version>9.3.11.v20160721</version>
                 <configuration>
                     <webApp>
-                        <contextPath>/front-controller</contextPath>
+                        <contextPath>/</contextPath>
                     </webApp>
                 </configuration>
             </plugin>

patterns/src/main/java/com/baeldung/enterprise/patterns/front/controller/FrontControllerServlet.java

@@ -1,38 +0,0 @@
-package com.baeldung.enterprise.patterns.front.controller;
-
-import com.baeldung.enterprise.patterns.front.controller.commands.FrontCommand;
-import com.baeldung.enterprise.patterns.front.controller.commands.UnknownCommand;
-
-import javax.servlet.ServletException;
-import javax.servlet.http.HttpServlet;
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
-
-public class FrontControllerServlet extends HttpServlet {
-    @Override
-    protected void doGet(
-      HttpServletRequest request,
-      HttpServletResponse response
-    ) throws ServletException, IOException {
-        FrontCommand command = getCommand(request);
-        command.init(getServletContext(), request, response);
-        command.process();
-    }
-
-    private FrontCommand getCommand(HttpServletRequest request) {
-        try {
-            Class type = Class.forName(
-              String.format(
-                "com.baeldung.enterprise.patterns.front.controller.commands.%sCommand",
-                request.getParameter("command")
-              )
-            );
-            return (FrontCommand) type
-              .asSubclass(FrontCommand.class)
-              .newInstance();
-        } catch (Exception e) {
-            return new UnknownCommand();
-        }
-    }
-}

patterns/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/FrontCommand.java

@@ -1,32 +0,0 @@
-package com.baeldung.enterprise.patterns.front.controller.commands;
-
-import javax.servlet.RequestDispatcher;
-import javax.servlet.ServletContext;
-import javax.servlet.ServletException;
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
-
-public abstract class FrontCommand {
-    protected ServletContext context;
-    protected HttpServletRequest request;
-    protected HttpServletResponse response;
-
-    public void init(
-      ServletContext servletContext,
-      HttpServletRequest servletRequest,
-      HttpServletResponse servletResponse
-    ) {
-        this.context = servletContext;
-        this.request = servletRequest;
-        this.response = servletResponse;
-    }
-
-    public abstract void process() throws ServletException, IOException;
-
-    protected void forward(String target) throws ServletException, IOException {
-        target = String.format("/WEB-INF/jsp/%s.jsp", target);
-        RequestDispatcher dispatcher = context.getRequestDispatcher(target);
-        dispatcher.forward(request, response);
-    }
-}

patterns/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/SearchCommand.java

@@ -1,21 +0,0 @@
-package com.baeldung.enterprise.patterns.front.controller.commands;
-
-import com.baeldung.enterprise.patterns.front.controller.data.Book;
-import com.baeldung.enterprise.patterns.front.controller.data.BookshelfImpl;
-
-import javax.servlet.ServletException;
-import java.io.IOException;
-
-public class SearchCommand extends FrontCommand {
-    @Override
-    public void process() throws ServletException, IOException {
-        Book book = new BookshelfImpl().getInstance()
-          .findByTitle(request.getParameter("title"));
-        if (book != null) {
-            request.setAttribute("book", book);
-            forward("book-found");
-        } else {
-            forward("book-notfound");
-        }
-    }
-}

patterns/src/main/java/com/baeldung/enterprise/patterns/front/controller/data/Bookshelf.java

@@ -1,15 +0,0 @@
-package com.baeldung.enterprise.patterns.front.controller.data;
-
-public interface Bookshelf {
-
-    default void init() {
-        add(new Book("Wilson, Robert Anton & Shea, Robert", "Illuminati", 9.99));
-        add(new Book("Fowler, Martin", "Patterns of Enterprise Application Architecture", 27.88));
-    }
-
-    Bookshelf getInstance();
-
-    <E extends Book> boolean add(E book);
-
-    Book findByTitle(String title);
-}

patterns/src/main/java/com/baeldung/enterprise/patterns/front/controller/data/BookshelfImpl.java

@@ -1,24 +0,0 @@
-package com.baeldung.enterprise.patterns.front.controller.data;
-
-import java.util.ArrayList;
-
-public class BookshelfImpl extends ArrayList<Book> implements Bookshelf {
-    private static Bookshelf INSTANCE;
-
-    @Override
-    public Bookshelf getInstance() {
-        if (INSTANCE == null) {
-            INSTANCE = new BookshelfImpl();
-            INSTANCE.init();
-        }
-        return INSTANCE;
-    }
-
-    @Override
-    public Book findByTitle(String title) {
-        return this.stream()
-          .filter(book -> book.getTitle().toLowerCase().contains(title.toLowerCase()))
-          .findFirst()
-          .orElse(null);
-    }
-}

patterns/src/main/java/com/baeldung/patterns/FrontControllerServlet.java

@@ -0,0 +1,66 @@
+package com.baeldung.patterns;
+
+import com.baeldung.patterns.commands.FrontCommand;
+import com.baeldung.patterns.commands.UnknownCommand;
+import com.baeldung.patterns.data.Bookshelf;
+import com.baeldung.patterns.data.BookshelfImpl;
+
+import javax.servlet.ServletConfig;
+import javax.servlet.ServletException;
+import javax.servlet.annotation.WebServlet;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+
+@WebServlet(name = "front-controller", urlPatterns = "/index")
+public class FrontControllerServlet extends HttpServlet {
+    @Override
+    public void init(ServletConfig config) throws ServletException {
+        super.init(config);
+        Bookshelf bookshelf = new BookshelfImpl();
+        bookshelf.init();
+        getServletContext().setAttribute("bookshelf", bookshelf);
+    }
+
+    @Override
+    protected void doGet(
+      HttpServletRequest request,
+      HttpServletResponse response
+    ) throws ServletException, IOException {
+        doCommand(request, response);
+    }
+
+    @Override
+    protected void doPost(
+      HttpServletRequest request,
+      HttpServletResponse response
+    ) throws ServletException, IOException {
+          doCommand(request, response);
+    }
+
+    private void doCommand(
+      HttpServletRequest request,
+      HttpServletResponse response
+    ) throws ServletException, IOException {
+        FrontCommand command = getCommand(request);
+        command.init(request, response);
+        command.process();
+    }
+
+    private FrontCommand getCommand(HttpServletRequest request) {
+        try {
+            Class type = Class.forName(
+              String.format(
+                "com.baeldung.patterns.commands.%sCommand",
+                request.getParameter("command")
+              )
+            );
+            return (FrontCommand) type
+              .asSubclass(FrontCommand.class)
+              .newInstance();
+        } catch (Exception e) {
+            return new UnknownCommand();
+        }
+    }
+}