BAEL-325: Massive extensions to the example from BAEL-305.

enterprise-patterns/intercepting-filter-pattern/pom.xml

@@ -37,7 +37,7 @@
             <plugin>
                 <groupId>org.eclipse.jetty</groupId>
                 <artifactId>jetty-maven-plugin</artifactId>
-                <version>9.3.11.v20160721</version>
+                <version>9.4.0.M1</version>
                 <configuration>
                     <webApp>
                         <contextPath>/intercepting-filter</contextPath>

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/FrontControllerServlet.java

@@ -2,7 +2,10 @@ 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 com.baeldung.enterprise.patterns.front.controller.data.Bookshelf;
+import com.baeldung.enterprise.patterns.front.controller.data.BookshelfImpl;
 
+import javax.servlet.ServletConfig;
 import javax.servlet.ServletException;
 import javax.servlet.annotation.WebServlet;
 import javax.servlet.http.HttpServlet;
@@ -10,8 +13,16 @@ import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
 
-@WebServlet(name = "front-controller", urlPatterns = "/")
+@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,

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/CheckoutCommand.java

@@ -0,0 +1,27 @@
+package com.baeldung.enterprise.patterns.front.controller.commands;
+
+import com.baeldung.enterprise.patterns.front.controller.data.Order;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpSession;
+import java.io.IOException;
+
+public class CheckoutCommand extends FrontCommand {
+    @Override
+    public void process() throws ServletException, IOException {
+        super.process();
+        HttpSession session = request.getSession(false);
+        if (request.getMethod().equals("POST")) {
+            session.removeAttribute("order");
+            response.sendRedirect("index?command=Home&message=Thank you for buying!");
+        } else {
+            Order order = (Order) session.getAttribute("order");
+            Double total = order.getItems().entrySet().stream()
+              .map(entry -> entry.getKey().getPrice() * entry.getValue())
+              .reduce((p1, p2) -> p1 + p2)
+              .orElse(0.00);
+            request.setAttribute("total", total);
+            forward("shopping-cart");
+        }
+    }
+}

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/HomeCommand.java

@@ -0,0 +1,17 @@
+package com.baeldung.enterprise.patterns.front.controller.commands;
+
+import com.baeldung.enterprise.patterns.front.controller.data.Bookshelf;
+
+import javax.servlet.ServletException;
+import java.io.IOException;
+
+public class HomeCommand extends FrontCommand {
+    @Override
+    public void process() throws ServletException, IOException {
+        super.process();
+        Bookshelf bookshelf = (Bookshelf) request.getServletContext()
+          .getAttribute("bookshelf");
+        request.setAttribute("books", bookshelf);
+        forward("home");
+    }
+}

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/LoginCommand.java

@@ -7,14 +7,14 @@ import java.io.IOException;
 public class LoginCommand extends FrontCommand {
     @Override
     public void process() throws ServletException, IOException {
-        if (request.getMethod().equals("GET")) {
-            request.setAttribute("redirect", request.getRequestURL()
-              .append("?").append(request.getQueryString()).toString());
-            forward("login");
-        } else {
+        if (request.getMethod().equals("POST")) {
             HttpSession session = request.getSession(true);
             session.setAttribute("username", request.getParameter("username"));
             response.sendRedirect(request.getParameter("redirect"));
+        } else {
+            request.setAttribute("redirect", request.getRequestURL()
+              .append("?").append(request.getQueryString()).toString());
+            forward("login");
         }
     }
 }

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/LogoutCommand.java

@@ -0,0 +1,16 @@
+package com.baeldung.enterprise.patterns.front.controller.commands;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpSession;
+import java.io.IOException;
+
+public class LogoutCommand extends FrontCommand {
+    @Override
+    public void process() throws ServletException, IOException {
+        super.process();
+        HttpSession session = request.getSession(false);
+        session.removeAttribute("username");
+        session.removeAttribute("order");
+        response.sendRedirect("index?command=Home");
+    }
+}

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/OrderCommand.java

@@ -0,0 +1,33 @@
+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.Bookshelf;
+import com.baeldung.enterprise.patterns.front.controller.data.Order;
+import com.baeldung.enterprise.patterns.front.controller.data.OrderImpl;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpSession;
+import java.io.IOException;
+
+public class OrderCommand extends FrontCommand {
+    @Override
+    public void process() throws ServletException, IOException {
+        super.process();
+        if (request.getMethod().equals("POST")) {
+            HttpSession session = request.getSession(false);
+            Order order = (Order) session.getAttribute("order");
+            if (order == null) {
+                String username = (String) session.getAttribute("username");
+                order = new OrderImpl(username);
+            }
+            Bookshelf bookshelf = (Bookshelf) request.getServletContext()
+              .getAttribute("bookshelf");
+            String isbn = request.getParameter("isbn");
+            Integer quantity = Integer.parseInt(request.getParameter("quantity"));
+            Book book = bookshelf.get(isbn);
+            order.add(book, quantity);
+            session.setAttribute("order", order);
+            response.sendRedirect(String.format("index?command=Show&isbn=%s", isbn));
+        }
+    }
+}

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/SearchCommand.java

@@ -1,19 +1,22 @@
 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 com.baeldung.enterprise.patterns.front.controller.data.Bookshelf;
 
 import javax.servlet.ServletException;
 import java.io.IOException;
+import java.util.List;
 
 public class SearchCommand extends FrontCommand {
     @Override
     public void process() throws ServletException, IOException {
         super.process();
-        Book book = new BookshelfImpl().getInstance()
-          .findByTitle(request.getParameter("title"));
-        if (book != null) {
-            request.setAttribute("book", book);
+        Bookshelf bookshelf = (Bookshelf) request.getServletContext()
+          .getAttribute("bookshelf");
+        String q = request.getParameter("q");
+        List<Book> books = bookshelf.find(q);
+        if (books.size() > 0) {
+            request.setAttribute("books", books);
             forward("book-found");
         } else {
             forward("book-notfound");

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/ShowCommand.java

@@ -0,0 +1,21 @@
+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.Bookshelf;
+
+import javax.servlet.ServletException;
+import java.io.IOException;
+import java.util.Collections;
+
+public class ShowCommand extends FrontCommand {
+    @Override
+    public void process() throws ServletException, IOException {
+        super.process();
+        Bookshelf bookshelf = (Bookshelf) request.getServletContext()
+          .getAttribute("bookshelf");
+        String title = request.getParameter("isbn");
+        Book book = bookshelf.get(title);
+        request.setAttribute("books", Collections.singletonList(book));
+        forward("book-found");
+    }
+}

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/commands/UnknownCommand.java

@@ -6,6 +6,7 @@ import java.io.IOException;
 public class UnknownCommand extends FrontCommand {
     @Override
     public void process() throws ServletException, IOException {
+        super.process();
         forward("unknown");
     }
 }

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/data/Book.java

@@ -1,6 +1,10 @@
 package com.baeldung.enterprise.patterns.front.controller.data;
 
 public interface Book {
+    String getIsbn();
+
+    void setIsbn(String isbn);
+
     String getAuthor();
 
     void setAuthor(String author);

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/data/BookImpl.java

@@ -1,6 +1,7 @@
 package com.baeldung.enterprise.patterns.front.controller.data;
 
 public class BookImpl implements Book {
+    private String isbn;
     private String author;
     private String title;
     private Double price;
@@ -8,12 +9,23 @@ public class BookImpl implements Book {
     public BookImpl() {
     }
 
-    public BookImpl(String author, String title, Double price) {
+    public BookImpl(String isbn, String author, String title, Double price) {
+        this.isbn = isbn;
         this.author = author;
         this.title = title;
         this.price = price;
     }
 
+    @Override
+    public String getIsbn() {
+        return isbn;
+    }
+
+    @Override
+    public void setIsbn(String isbn) {
+        this.isbn = isbn;
+    }
+
     @Override
     public String getAuthor() {
         return author;

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/data/Bookshelf.java

@@ -1,16 +1,18 @@
 package com.baeldung.enterprise.patterns.front.controller.data;
 
+import java.util.List;
+
 public interface Bookshelf {
 
     default void init() {
-        add(new BookImpl("Wilson, Robert Anton & Shea, Robert", "Illuminati", 9.99));
-        add(new BookImpl("Fowler, Martin", "Patterns of Enterprise Application Architecture", 27.88));
-        add(new BookImpl("Unknown", "Something about German Umlauts (äüö) and ß", 5.49));
+        add(new BookImpl("001", "Wilson, Robert Anton & Shea, Robert", "Illuminati", 9.99));
+        add(new BookImpl("002", "Fowler, Martin", "Patterns of Enterprise Application Architecture", 27.88));
+        add(new BookImpl("003", "Unknown", "Something about German Umlauts (äüö) and ß", 5.49));
     }
 
-    Bookshelf getInstance();
-
     <E extends Book> boolean add(E book);
 
-    Book findByTitle(String title);
+    Book get(String isbn);
+
+    List<Book> find(String q);
 }

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/data/BookshelfImpl.java

@@ -1,24 +1,23 @@
 package com.baeldung.enterprise.patterns.front.controller.data;
 
 import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
 
 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) {
+    public Book get(String isbn) {
         return this.stream()
-          .filter(book -> book.getTitle().toLowerCase().contains(title.toLowerCase()))
+          .filter(book -> book.getIsbn().equals(isbn))
           .findFirst()
           .orElse(null);
     }
+
+    @Override
+    public List<Book> find(String q) {
+        return this.stream()
+          .filter(book -> book.getTitle().toLowerCase().contains(q.toLowerCase())
+            || book.getAuthor().toLowerCase().contains(q.toLowerCase()))
+          .collect(Collectors.toList());
+    }
 }

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/data/Order.java

@@ -0,0 +1,11 @@
+package com.baeldung.enterprise.patterns.front.controller.data;
+
+import java.util.Map;
+
+public interface Order {
+    String getUsername();
+
+    Map<Book, Integer> getItems();
+
+    void add(Book item, Integer quantity);
+}

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/data/OrderImpl.java

@@ -0,0 +1,40 @@
+package com.baeldung.enterprise.patterns.front.controller.data;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class OrderImpl implements Order {
+    private String username;
+    private Map<Book, Integer> items = new HashMap<>();
+
+    public OrderImpl(String username) {
+        this.username = username;
+    }
+
+    @Override
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    @Override
+    public Map<Book, Integer> getItems() {
+        return items;
+    }
+
+    public void setItems(Map<Book, Integer> items) {
+        this.items = items;
+    }
+
+    @Override
+    public void add(Book item, Integer quantity) {
+        Integer q = 0;
+        if (this.items.containsKey(item)) {
+            q = this.items.get(item);
+        }
+        this.items.put(item, quantity + q);
+    }
+}

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/filters/AuthenticationFilter.java

@@ -29,10 +29,10 @@ public class AuthenticationFilter extends BaseFilter {
         HttpServletResponse httpServletResponse = (HttpServletResponse) response;
         HttpSession session = httpServletRequest.getSession(false);
         if (session == null || session.getAttribute("username") == null) {
+            callback.intercept();
             FrontCommand command = new LoginCommand();
             command.init(httpServletRequest, httpServletResponse);
             command.process();
-            callback.intercept();
         } else {
             chain.doFilter(request, response);
         }

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/filters/FilterManager.java

@@ -14,7 +14,7 @@ public class FilterManager {
     ) throws ServletException, IOException {
         FilterChain filterChain = new FilterChainImpl(
           new AuthenticationFilter(callback),
-          new AuditFilter()
+          new VisitorCounterFilter()
         );
         filterChain.doFilter(request, response);
     }

enterprise-patterns/intercepting-filter-pattern/src/main/java/com/baeldung/enterprise/patterns/front/controller/filters/LoggingFilter.java

@@ -24,16 +24,10 @@ public class LoggingFilter extends BaseFilter {
         chain.doFilter(request, response);
         HttpServletRequest httpServletRequest = (HttpServletRequest) request;
         String username = (String) httpServletRequest.getAttribute("username");
-        if (username != null && username.length() > 0) {
-            username = username.concat("@");
-        } else {
-            username = "";
+        if (username == null) {
+            username = "guest";
         }
-        String intro = "Request";
-        if (username.length() > 0) {
-            intro = "Authenticated request";
-        }
-        log.info("{} from '{}{}': {}?{}", intro, username, request.getRemoteAddr(),
+        log.info("Request from '{}@{}': {}?{}", username, request.getRemoteAddr(),
           httpServletRequest.getRequestURI(), request.getParameterMap());
     }
 }

enterprise-patterns/intercepting-filter-pattern/src/main/webapp/WEB-INF/jsp/book-found.jsp

@@ -1,13 +1,24 @@
+<%@ page import="com.baeldung.enterprise.patterns.front.controller.data.Book" %>
+<%@ page import="java.util.List" %>
 <!DOCTYPE html>
 <html>
     <head>
         <title>Bookshelf: Title found</title>
     </head>
     <body>
-        <p>Our Bookshelf contains this title:</p>
-        <h2>${book.getTitle()}</h2>
-        <p>Author: ${book.getAuthor()}</p>
-        <input type="submit" value="Buy it: ${book.getPrice()}$">
+        <p>Our Bookshelf contains following titles:</p>
+        <% for (Book book : (List<Book>) request.getAttribute("books")) { %>
+            <h2><%= book.getTitle() %></h2>
+            <p>Author: <%= book.getAuthor() %></p>
+            <form action="index?command=Order" method="POST">
+                <label for="quantity">Quantity:</label>
+                <input type="text" id="quantity" name="quantity" value="1" required>
+                <input type="hidden" name="isbn" value="<%= book.getIsbn() %>">
+                <input type="submit" value="Buy it: <%= book.getPrice() %>$">
+                <a href="index?command=Home">Go back...</a>
+            </form>
+        <% } %>
+        <%@ include file="shopping-cart-hint.jsp"%>
         <%@ include file="visitor-counter.jsp"%>
     </body>
 </html>

enterprise-patterns/intercepting-filter-pattern/src/main/webapp/WEB-INF/jsp/book-notfound.jsp

@@ -5,7 +5,7 @@
     </head>
     <body>
         <p>Our Bookshelf doesn't contains this title:</p>
-        <h2>${param.get("title")}</h2>
+        <h2><%= request.getParameter("q") %></h2>
         <%@ include file="visitor-counter.jsp"%>
     </body>
 </html>

enterprise-patterns/intercepting-filter-pattern/src/main/webapp/WEB-INF/jsp/home.jsp

@@ -0,0 +1,27 @@
+<%@ page import="com.baeldung.enterprise.patterns.front.controller.data.Book" %>
+<%@ page import="java.util.List" %>
+<!DOCTYPE>
+<html>
+    <head>
+        <title>Bookshelf: Home</title>
+    </head>
+    <body>
+        <form action="index?command=Search" method="POST">
+            <input type="text" id="search" name="q">
+            <input type="submit" value="Go!">
+        </form>
+        <% if (request.getParameter("message") != null) { %>
+            <h2><%= request.getParameter("message") %></h2>
+        <% } else { %>
+            <h2>Welcome to the Bookshelf!</h2>
+        <% } %>
+        <% for (Book book : (List<Book>) request.getAttribute("books")) { %>
+            <hr/>
+            <p><b><%= book.getAuthor() %>:</b></p>
+            <h3><%= book.getTitle() %></h3>
+            <a href="index?command=Show&isbn=<%= book.getIsbn() %>">More...</a>
+        <% } %>
+        <%@ include file="shopping-cart-hint.jsp"%>
+        <%@ include file="visitor-counter.jsp"%>
+    </body>
+</html>

enterprise-patterns/intercepting-filter-pattern/src/main/webapp/WEB-INF/jsp/login.jsp

@@ -6,10 +6,11 @@
     <body>
         <p>Please input a username:</p>
         <h2>Login</h2>
-        <form action="/intercepting-filter/?command=Login" method="POST">
+        <form action="index?command=Login" method="POST">
             <input type="text" name="username" placeholder="Username">
-            <input type="hidden" name="redirect" value="${redirect}">
+            <input type="hidden" name="redirect" value="<%= (String) request.getAttribute("redirect") %>">
             <input type="submit" value="Proceed">
         </form>
+        <%@ include file="visitor-counter.jsp" %>
     </body>
 </html>

enterprise-patterns/intercepting-filter-pattern/src/main/webapp/WEB-INF/jsp/shopping-cart-hint.jsp

@@ -0,0 +1,16 @@
+<%@ page import="com.baeldung.enterprise.patterns.front.controller.data.Order" %>
+<% if (session != null && session.getAttribute("order") != null) { %>
+    <% Order order = ((Order) session.getAttribute("order")); %>
+    <% if (order != null && order.getItems().size() > 0) { %>
+        <hr/>
+        <p>
+            Your shopping cart is holding
+            <% if (order.getItems().size() == 1) { %>
+                1 item.
+            <% } else { %>
+                <%= (order.getItems().size()) %> items.
+            <% } %>
+            <a href="index?command=Checkout">Checkout</a>
+        </p>
+    <% } %>
+<% } %>

enterprise-patterns/intercepting-filter-pattern/src/main/webapp/WEB-INF/jsp/shopping-cart.jsp

@@ -0,0 +1,29 @@
+<%@ page import="com.baeldung.enterprise.patterns.front.controller.data.Book" %>
+<%@ page import="com.baeldung.enterprise.patterns.front.controller.data.Order" %>
+<%@ page import="java.util.Map" %>
+<!DOCTYPE html>
+<html>
+    <head>
+        <title>Bookshelf: Checkout</title>
+    </head>
+    <body>
+        <p>You are about to buy the following books:</p>
+        <h2>Shopping Cart</h2>
+        <% Order order = (Order) session.getAttribute("order"); %>
+        <ul>
+            <% for (Map.Entry<Book, Integer> entry : order.getItems().entrySet()) { %>
+                <li>
+                    <b><%= entry.getValue() %> x <%= entry.getKey().getPrice() %></b>
+                    <h3><%= entry.getKey().getTitle() %></h3>
+                    <i> by <%= entry.getKey().getAuthor()%></i>
+                </li>
+            <% } %>
+        </ul>
+        <p>
+            <b>Total: <%= request.getAttribute("total") %></b>
+        </p>
+        <form action="index?command=Checkout" method="POST">
+            <input type="submit" value="Donate :)">
+        </form>
+    </body>
+</html>

enterprise-patterns/intercepting-filter-pattern/src/main/webapp/WEB-INF/jsp/unknown.jsp

@@ -5,6 +5,5 @@
     </head>
     <body>
         <p>Sorry, this command is not known!</p>
-        <%@include file="visitor-counter.jsp"%>
     </body>
 </html>

enterprise-patterns/intercepting-filter-pattern/src/main/webapp/WEB-INF/jsp/visitor-counter.jsp

@@ -1,2 +1,5 @@
+<% Integer counter = (Integer) request.getAttribute("counter"); %>
+<% if (counter != null && counter > 0) { %>
     <hr/>
-<p>You are visitor #${counter}!</p>
+    <p>You are visitor #<%= counter %>. <a href="index?command=Logout">Logout</a></p>
+<% } %>