Reorganised projects

15 files changed, 1663 insertions, 0 deletions

diff --git a/Week9 Webshop/src/com/camilstaps/shop/Article.java b/Week9 Webshop/src/com/camilstaps/shop/Article.java
new file mode 100644
index 0000000..d22a323
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/Article.java
@@ -0,0 +1,89 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+import java.io.File;
+
+/**
+ * An Article in the webshop
+ * @author Camil Staps, s4498062
+ */
+public class Article extends DatabaseItem {
+
+    /**
+     * Basic data about the article
+     */
+    private final String name;
+    private String description;
+    private final Category category;
+    private File multimedia;
+    private final float price;
+    
+    /**
+     * The owner who added the article
+     */
+    private final User owner;
+
+    /**
+     * Straightforwardly creating a new article
+     * @param user
+     * @param name
+     * @param category
+     * @param price
+     */
+    public Article(User user, String name, Category category, float price) {
+        this.owner = user;
+        this.name = name;
+        this.category = category;
+        this.price = price;
+    }
+    
+    public User getOwner() {
+        return owner;
+    }
+    
+    public String getName() {
+        return name;
+    }
+    
+    public String getDescription() {
+        return description;
+    }
+    
+    public Category getCategory() {
+        return category;
+    }
+    
+    public File getMultimedia() {
+        return multimedia;
+    }
+    
+    public float getPrice() {
+        return price;
+    }
+
+    /**
+     * Set a new description
+     * @param description
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Set multimedia
+     * @param multimedia
+     */
+    public void setMultimedia(File multimedia) {
+        this.multimedia = multimedia;
+    }
+    
+    @Override
+    public String toString() {
+        return name + " (" + category.getName() + "): " + Float.toString(price);
+    }
+
+}
\ No newline at end of file
diff --git a/Week9 Webshop/src/com/camilstaps/shop/CLIInteraction.java b/Week9 Webshop/src/com/camilstaps/shop/CLIInteraction.java
new file mode 100644
index 0000000..cbf59ab
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/CLIInteraction.java
@@ -0,0 +1,94 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+import java.io.InputStream;
+import java.io.PrintStream;
+import java.util.InputMismatchException;
+import java.util.Scanner;
+
+/**
+ * Command Line Interface Interaction
+ * @author Camil Staps, s4498062
+ */
+public class CLIInteraction extends UserInteraction {
+    
+    private final Scanner in;
+    private final PrintStream out;
+    
+    /**
+     * Default is stdin and stdout
+     */
+    public CLIInteraction() {
+        this(System.in, System.out);
+    }
+    
+    /**
+     * CLI interaction with custom input and outputstream
+     * @param is
+     * @param ps 
+     */
+    public CLIInteraction(InputStream is, PrintStream ps) {
+        in = new Scanner(is);
+        out = ps;
+    }
+
+    @Override
+    String getString() {
+        return in.nextLine();
+    }
+
+    @Override
+    public int getChoice(String question, String[] options) {
+        out.println(question);
+        int i = 1;
+        for (String option : options) {
+            out.println("  " + (i++) + " : " + option);
+        }
+        int selection = 0;
+        boolean read = false;
+        do {
+            if (read) {
+                out.println("Invalid option. Try again:");
+            }
+            try {
+                selection = in.nextInt();
+            } catch (InputMismatchException ex) {
+            }
+            in.nextLine();
+            read = true;
+        } while (selection < 1 || selection > options.length);
+        return selection - 1;
+    }
+
+    @Override
+    void putString(String string) {
+        out.print(string);
+    }
+
+    @Override
+    Command getCommand() {
+        putString("► ");
+        return new Command(getString());
+    }
+
+    @Override
+    float getFloat() {
+        float result = in.nextFloat();
+        in.nextLine();
+        return result;
+    }
+
+    @Override
+    boolean getBoolean() {
+        putString(" (yes/no) ");
+        String result;
+        do {
+            result = in.nextLine();
+        } while (!result.equalsIgnoreCase("yes") && !result.equalsIgnoreCase("no"));
+        return result.equalsIgnoreCase("yes");
+    }
+}
\ No newline at end of file
diff --git a/Week9 Webshop/src/com/camilstaps/shop/Cart.java b/Week9 Webshop/src/com/camilstaps/shop/Cart.java
new file mode 100644
index 0000000..74f6ccd
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/Cart.java
@@ -0,0 +1,67 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+import java.io.Serializable;
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * A Cart holds the articles a User is planning to buy.
+ * @author Camil Staps, s4498062
+ */
+public class Cart implements Serializable {
+    
+    private final Set<Article> articles = new HashSet<>();
+    
+    public Set<Article> getArticles() {
+        return articles;
+    }
+
+    /**
+     * Get the total price of all articles
+     * @return 
+     */
+    public float getTotalAmount() {
+        float result = 0;
+        for (Article a : articles) {
+            result += a.getPrice();
+        }
+        return result;
+    }
+
+    /**
+     * Add a new article
+     * @param article
+     */
+    public void add(Article article) {
+        Database.getInstance().removeItem(article);
+        articles.add(article);
+    }
+
+    /**
+     * Remove an article (and put it back in the database)
+     * @param article
+     */
+    public void remove(Article article) {
+        articles.remove(article);
+        try {
+            Database.getInstance().addItem(article);
+        } catch (DuplicateEntryException ex) {
+        }
+    }
+    
+    /**
+     * Remove all articles in the manner of remove()
+     * @see self#remove
+     */
+    public void reset() {
+        for (Article a : articles) {
+            remove(a);
+        }
+    }
+
+}
\ No newline at end of file
diff --git a/Week9 Webshop/src/com/camilstaps/shop/Category.java b/Week9 Webshop/src/com/camilstaps/shop/Category.java
new file mode 100644
index 0000000..05c247c
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/Category.java
@@ -0,0 +1,28 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+/**
+ * A Category for Articles
+ * @author Camil Staps, s4498062
+ */
+public class Category extends DatabaseItem {
+
+    private final String name;
+
+    /**
+     * Create a new Category
+     * @param name
+     */
+    public Category(String name) {
+        this.name = name;
+    }
+    
+    public String getName() {
+        return name;
+    }
+
+}
\ No newline at end of file
diff --git a/Week9 Webshop/src/com/camilstaps/shop/Command.java b/Week9 Webshop/src/com/camilstaps/shop/Command.java
new file mode 100644
index 0000000..b4694c0
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/Command.java
@@ -0,0 +1,25 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+/**
+ * A Command is something that can be executed by a normal visitor, a User or an Administrator.
+ * The current version only holds one string as command, but later versions could include arguments.
+ * @author Camil Staps, s4498062
+ */
+public class Command {
+    
+    private final String command;
+    
+    public Command(String command) {
+        this.command = command;
+    }
+    
+    public String getCommand() {
+        return command;
+    }
+    
+}
diff --git a/Week9 Webshop/src/com/camilstaps/shop/Database.java b/Week9 Webshop/src/com/camilstaps/shop/Database.java
new file mode 100644
index 0000000..8344bca
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/Database.java
@@ -0,0 +1,393 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.regex.Pattern;
+
+/**
+ * The Shop database
+ * @author Camil Staps, s4498062
+ */
+public class Database {
+    
+    /**
+     * This is a singleton
+     */
+    private static Database instance;
+
+    /**
+     * Keep the database in working memory during runtime
+     */
+    private Set<User> users;
+    private Set<Article> articles;
+    private Set<Category> categories;
+    private Set<Order> orders;
+    
+    /**
+     * Files to store the database
+     * Considering backups, it's nicer to have different objects stored in 
+     * different files, so that if the Orders file breaks, we still have the
+     * Users, etc.
+     */
+    private final File FILE_DB = new File("./db");
+    private final File FILE_USERS = new File("./db/users.db");
+    private final File FILE_ARTICLES = new File("./db/articles.db");
+    private final File FILE_CATEGORIES = new File("./db/categories.db");
+    private final File FILE_ORDERS = new File("./db/orders.db");
+    
+    /**
+     * Don't use this constructor. This is a singleton: use getInstance() instead.
+     * @see self#getInstance()
+     */
+    public Database() {
+        if (!FILE_DB.exists())
+            FILE_DB.mkdir();
+        
+        readUsers();
+        readArticles();
+        readCategories();
+        readOrders();
+    }
+
+    /**
+     * Get an instance of the database. This is a singleton.
+     * @return the database
+     */
+    public static Database getInstance() {
+        if (instance == null) {
+            instance = new Database();
+        }
+        return instance;
+    }
+
+    /**
+     * Add an item to the database
+     * @param item the item
+     * @throws com.camilstaps.shop.DuplicateEntryException
+     * @throws ClassCastException if the item to remove is not a DatabaseItem
+     */
+    public void addItem(DatabaseItem item) throws DuplicateEntryException {
+        if (item instanceof User) {
+            if (isUserExists(((User) item).getNr())) {
+                throw new DuplicateEntryException();
+            }
+            users.add((User) item);
+        } else if (item instanceof Article) {
+            if (isArticleExists(((Article) item).getName())) {
+                throw new DuplicateEntryException();
+            }
+            articles.add((Article) item);
+        } else if (item instanceof Category) {
+            if (isCategoryExists(((Category) item).getName())) {
+                throw new DuplicateEntryException();
+            }
+            categories.add((Category) item);
+        } else if (item instanceof Order) {
+            orders.add((Order) item);
+        } else {
+            throw new ClassCastException();
+        }
+    }
+
+    /**
+     * Remove an item from the database
+     * @param item the item to remove
+     * @throws ClassCastException if the item to remove is not a DatabaseItem
+     */
+    public void removeItem(DatabaseItem item) {
+        if (item instanceof User) {
+            users.remove((User) item);
+        } else if (item instanceof Article) {
+            articles.remove((Article) item);
+        } else if (item instanceof Category) {
+            categories.remove((Category) item);
+        } else if (item instanceof Order) {
+            orders.remove((Order) item);
+        } else {
+            throw new ClassCastException();
+        }
+    }
+    
+    /**
+     * Save the database to the filesystem.
+     * @return true on success, false on failure
+     */
+    public boolean write() {
+        return writeUsers() && writeArticles() && writeCategories() && writeOrders();
+    }
+    
+    /**
+     * Check if there exists a user with a certain U/S-number
+     * @param nr
+     * @return 
+     */
+    public boolean isUserExists(String nr) {
+        for (User user : users) {
+            if (user.getNr().equals(nr)) {
+                return true;
+            }
+        }
+        return false;
+    }
+    
+    /**
+     * Check if an article with a name exists
+     * @param name
+     * @return 
+     */
+    public boolean isArticleExists(String name) {
+        for (Article article : articles) {
+            if (article.getName().equals(name)) {
+                return true;
+            }
+        }
+        return false;
+    }
+    
+    /**
+     * Check if a category with a name exists
+     * @param name
+     * @return 
+     */
+    public boolean isCategoryExists(String name) {
+        for (Category category : categories) {
+            if (category.getName().equals(name)) {
+                return true;
+            }
+        }
+        return false;
+    }
+    
+    /**
+     * Get the set of users
+     * @return 
+     */
+    public Set<User> getUsers() {
+        return users;
+    }
+    
+    /**
+     * Get the set of articles
+     * @return 
+     */
+    public Set<Article> getArticles() {
+        return articles;
+    }
+    
+    /**
+     * Get the set of categories
+     * @return 
+     */
+    public Set<Category> getCategories() {
+        return categories;
+    }
+    
+    /**
+     * Get an array of the names of the categories
+     * @return 
+     */
+    public String[] getCategoryNames() {
+        String[] categoryNames = new String[categories.size()];
+        int i = 0;
+        for (Category c : categories) {
+            categoryNames[i++] = c.getName();
+        }
+        return categoryNames;
+    }
+    
+    /**
+     * Get the set of orders
+     * @return 
+     */
+    public Set<Order> getOrders() {
+        return orders;
+    }
+    
+    /**
+     * Get the set of articles of which the name or description matches a regular expression
+     * @param p the regular expression
+     * @return 
+     */
+    public Set<Article> searchArticle(Pattern p) {
+        Set<Article> result = new HashSet<>();
+        for (Article a : articles) {
+            if (p.matcher(a.getName()).find() || p.matcher(a.getDescription()).find()) {
+                result.add(a);
+            }
+        }
+        return result;
+    }
+    
+    /**
+     * Get a user by his number
+     * @param number
+     * @return 
+     * @throws com.camilstaps.shop.ItemNotFoundException 
+     */
+    public User getUser(String number) throws ItemNotFoundException {
+        for (User u : users) {
+            if (u.getNr().equals(number)) {
+                return u;
+            }
+        }
+        throw new ItemNotFoundException();
+    }
+    
+    /**
+     * Get an article by its name
+     * @param name
+     * @return
+     * @throws ItemNotFoundException 
+     */
+    public Article getArticle(String name) throws ItemNotFoundException {
+        for (Article a : articles) {
+            if (a.getName().equals(name)) {
+                return a;
+            }
+        }
+        throw new ItemNotFoundException();
+    }
+    
+    /**
+     * Get a category by a name
+     * @param name
+     * @return 
+     */
+    public Category getCategory(String name) throws ItemNotFoundException {
+        for (Category c : categories) {
+            if (c.getName().equals(name)) {
+                return c;
+            }
+        }
+        throw new ItemNotFoundException();
+    }
+    
+    /**
+     * Read the users from the database into RAM
+     */
+    private void readUsers() {
+        users = new HashSet<>();
+        try (ObjectInputStream in = new ObjectInputStream(new FileInputStream(FILE_USERS))) {
+            users = (Set) in.readObject();
+            in.close();
+        } catch (FileNotFoundException ex) {
+        } catch (IOException | ClassNotFoundException ex) {
+        }
+    }
+    
+    /**
+     * Read the articles from the database into RAM
+     */
+    private void readArticles() {
+        articles = new HashSet<>();
+        try (ObjectInputStream in = new ObjectInputStream(new FileInputStream(FILE_ARTICLES))) {
+            articles = (Set) in.readObject();
+            in.close();
+        } catch (FileNotFoundException ex) {
+        } catch (IOException | ClassNotFoundException ex) {
+        }
+    }
+    
+    /**
+     * Read the categories from the database into RAM
+     */
+    private void readCategories() {
+        categories = new HashSet<>();
+        try (ObjectInputStream in = new ObjectInputStream(new FileInputStream(FILE_CATEGORIES))) {
+            categories = (Set) in.readObject();
+            in.close();
+        } catch (FileNotFoundException ex) {
+        } catch (IOException | ClassNotFoundException ex) {
+        }
+    }
+    
+    /**
+     * Read the orders from the database into RAM
+     */
+    private void readOrders() {
+        orders = new HashSet<>();
+        try (ObjectInputStream in = new ObjectInputStream(new FileInputStream(FILE_ORDERS))) {
+            orders = (Set) in.readObject();
+            in.close();
+        } catch (FileNotFoundException ex) {
+        } catch (IOException | ClassNotFoundException ex) {
+        }
+    }
+    
+    /**
+     * Write the users from RAM to the database 
+     */
+    private boolean writeUsers() {
+        System.err.println("Saving users...");
+        
+        try (ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(FILE_USERS))) {
+            out.writeObject(users);
+            out.close();
+            return true;
+        } catch (IOException ex) {
+            ex.printStackTrace();
+        }
+        return false;
+    }
+    
+    /**
+     * Write the articles from RAM to the database 
+     */
+    private boolean writeArticles() {
+        System.err.println("Saving articles...");
+        
+        try (ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(FILE_ARTICLES))) {
+            out.writeObject(articles);
+            out.close();
+            return true;
+        } catch (IOException ex) {
+            ex.printStackTrace();
+        }
+        return false;
+    }
+    
+    /**
+     * Write the categories from RAM to the database 
+     */
+    private boolean writeCategories() {
+        System.err.println("Saving categories...");
+        
+        try (ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(FILE_CATEGORIES))) {
+            out.writeObject(categories);
+            out.close();
+            return true;
+        } catch (IOException ex) {
+            ex.printStackTrace();
+        }
+        return false;
+    }
+    
+    /**
+     * Write the orders from RAM to the database 
+     */
+    private boolean writeOrders() {
+        System.err.println("Saving orders...");
+        
+        try (ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(FILE_ORDERS))) {
+            out.writeObject(orders);
+            out.close();
+            return true;
+        } catch (IOException ex) {
+            ex.printStackTrace();
+        }
+        return false;
+    }
+
+}
\ No newline at end of file
diff --git a/Week9 Webshop/src/com/camilstaps/shop/DatabaseItem.java b/Week9 Webshop/src/com/camilstaps/shop/DatabaseItem.java
new file mode 100644
index 0000000..0cbe661
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/DatabaseItem.java
@@ -0,0 +1,15 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+import java.io.Serializable;
+
+/**
+ * DatabaseItem is a general class for anything that is stored in the Database
+ * @author Camil Staps, s4498062
+ */
+public class DatabaseItem implements Serializable {
+}
\ No newline at end of file
diff --git a/Week9 Webshop/src/com/camilstaps/shop/DuplicateEntryException.java b/Week9 Webshop/src/com/camilstaps/shop/DuplicateEntryException.java
new file mode 100644
index 0000000..a91d7c7
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/DuplicateEntryException.java
@@ -0,0 +1,18 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+/**
+ * This Exception is thrown when an attempt is made to add a DatabaseItem to the
+ * Database which gives a uniqueness conflict, such as:
+ *  * An article with the same name exists
+ *  * A category with the same name exists
+ *  * A user with the same number exists
+ * 
+ * @author Camil Staps, s4498062
+ */
+public class DuplicateEntryException extends Exception {
+}
diff --git a/Week9 Webshop/src/com/camilstaps/shop/InputRequiredException.java b/Week9 Webshop/src/com/camilstaps/shop/InputRequiredException.java
new file mode 100644
index 0000000..ca0110d
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/InputRequiredException.java
@@ -0,0 +1,13 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+/**
+ * This Exception is thrown when required input was omitted by the user.
+ * @author Camil Staps, s4498062
+ */
+public class InputRequiredException extends Exception {
+}
diff --git a/Week9 Webshop/src/com/camilstaps/shop/ItemNotFoundException.java b/Week9 Webshop/src/com/camilstaps/shop/ItemNotFoundException.java
new file mode 100644
index 0000000..5122d79
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/ItemNotFoundException.java
@@ -0,0 +1,14 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+/**
+ * This error is thrown when an attempt is made to instantiate an object with a 
+ * non-existing name, number, etc.
+ * @author Camil Staps, s4498062
+ */
+public class ItemNotFoundException extends Exception {
+}
diff --git a/Week9 Webshop/src/com/camilstaps/shop/Order.java b/Week9 Webshop/src/com/camilstaps/shop/Order.java
new file mode 100644
index 0000000..2b0c5a7
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/Order.java
@@ -0,0 +1,67 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * An order is a set of articles, purchased by a user
+ * @author Camil Staps, s4498062
+ */
+public class Order extends DatabaseItem {
+    
+    private final Set<Article> articles;
+    private final User user;
+    private boolean paid = false;
+    
+    /**
+     * This constructor takes the articles from the Cart of the User, and clears 
+     * that Cart afterwards.
+     * @param user 
+     */
+    public Order(User user) {
+        this.user = user;
+        articles = new HashSet<>();
+        for (Article a : user.getCart().getArticles()) {
+            articles.add(a);
+        }
+        user.getCart().getArticles().clear();
+    }
+    
+    public User getUser() {
+        return user;
+    }
+    
+    public Set<Article> getArticles() {
+        return articles;
+    }
+    
+    public void setPaid(boolean set) {
+        paid = set;
+    }
+    
+    /**
+     * See whether payment has been received for this article already
+     * @return 
+     */
+    public boolean isPaid() {
+        return paid;
+    }
+    
+    /**
+     * Get the total price of all articles
+     * @return 
+     */
+    public float getTotalAmount() {
+        float result = 0;
+        for (Article a : articles) {
+            result += a.getPrice();
+        }
+        return result;
+    }
+    
+}
diff --git a/Week9 Webshop/src/com/camilstaps/shop/Shell.java b/Week9 Webshop/src/com/camilstaps/shop/Shell.java
new file mode 100644
index 0000000..7939963
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/Shell.java
@@ -0,0 +1,476 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+import java.io.File;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.Set;
+import java.util.regex.Pattern;
+
+/**
+ * Executing commands and providing output, using a UserInteraction and acting 
+ * on a Database.
+ * @author Camil Staps, s4498062
+ */
+public class Shell {
+    
+    /**
+     * The Database to work with
+     */
+    private final Database database;
+    /**
+     * The UserInteraction to use
+     */
+    private final UserInteraction ui;
+    
+    /**
+     * The current User, if logged in
+     */
+    private User user;
+    
+    public Shell(UserInteraction userInteraction) {
+        this.database = Database.getInstance();
+        this.ui = userInteraction;
+    }
+    
+    /**
+     * Request commands, execute them, and show the results
+     */
+    public void run() {
+        while (true) {
+            Command command = ui.getCommand();
+            try {
+                Method method = getClass().getMethod("exec" + command.getCommand().substring(0,1).toUpperCase() + command.getCommand().substring(1));
+                method.invoke(this);
+                
+                if (command.getCommand().equalsIgnoreCase("exit")) {
+                    return;
+                }
+            } catch (NoSuchMethodException ex) {
+                ui.putStringln("Failure: no such command");
+            } catch (InvocationTargetException ex) {
+                ui.putStringln("Failure: " + ex.getCause().toString());
+            } catch (SecurityException | IllegalAccessException | IllegalArgumentException ex) {
+                ui.putStringln("Failure: unknown error");
+            }
+        }
+    }
+    
+    /**
+     * Require that the visitor logs in
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException if the visitor fails to login
+     * @throws ItemNotFoundException if the visitor tries to login with a non-existing User number
+     */
+    public void requireLogin() throws LoginRequiredException, ItemNotFoundException {
+        if (user == null) {
+            ui.putStringln("You must login first.");
+            
+            try {
+                execLogin();
+            } catch (InputRequiredException ex) {
+            }
+            
+            if (user == null) {
+                throw new LoginRequiredException();
+            }
+        }
+    }
+    
+    /**
+     * Require that an administrator is logged in
+     * @throws com.camilstaps.shop.Shell.AdminRequiredException if the visitor fails to login, or is not an administrator
+     * @throws ItemNotFoundException if the visitor tries to login with a non-existing User number
+     */
+    public void requireAdmin() throws AdminRequiredException, ItemNotFoundException {
+        if (user == null || !user.isAdmin()) {
+            ui.putStringln("You must login as an administrator first.");
+            
+            try {
+                execLogin();
+            } catch (InputRequiredException ex) {
+            }
+                
+            if (user == null || !user.isAdmin()) {
+                throw new AdminRequiredException();
+            }
+        }
+    }
+    
+    /**
+     * Command: add an article
+     * @throws DuplicateEntryException
+     * @throws InputRequiredException
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws ItemNotFoundException 
+     */
+    public void execAddArticle() throws DuplicateEntryException, InputRequiredException, LoginRequiredException, ItemNotFoundException {
+        requireLogin();
+        
+        String name = ui.getRequiredString("Name: ");
+        Category category = ui.getCategory();
+        float price = ui.getFloat("Price: ");
+        
+        Article a = new Article(user, name, category, price);
+        database.addItem(a);
+    }
+    
+    /**
+     * Command: set the article description
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws ItemNotFoundException
+     * @throws InputRequiredException 
+     */
+    public void execSetArticleDescription() throws LoginRequiredException, ItemNotFoundException, InputRequiredException {
+        requireLogin();
+        
+        Article a;
+        if (user.isAdmin()) {
+            a = ui.getArticle();
+        } else {
+            a = ui.getArticle(user);
+        }
+        
+        a.setDescription(ui.getRequiredString("Description: "));
+    }
+    
+    /**
+     * Command: set the multimedia linked to an article
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws ItemNotFoundException
+     * @throws InputRequiredException 
+     */
+    public void execSetArticleMultimedia() throws LoginRequiredException, ItemNotFoundException, InputRequiredException {
+        requireLogin();
+        
+        Article a;
+        if (user.isAdmin()) {
+            a = ui.getArticle();
+        } else {
+            a = ui.getArticle(user);
+        }
+        
+        a.setMultimedia(new File(ui.getRequiredString("Multimedia: ")));
+    }
+    
+    /**
+     * Command: remove an article
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws ItemNotFoundException
+     * @throws InputRequiredException 
+     */
+    public void execRemoveArticle() throws LoginRequiredException, ItemNotFoundException, InputRequiredException {
+        requireLogin();
+        
+        Article a;
+        if (user.isAdmin()) {
+            a = ui.getArticle();
+        } else {
+            a = ui.getArticle(user);
+        }
+        
+        database.removeItem(a);
+    }
+    
+    /**
+     * Command: show a list of articles
+     */
+    public void execListArticles() {
+        for (Article a : database.getArticles()) {
+            ui.putStringln(a.toString());
+        }
+    }
+    
+    /**
+     * Command: search for an article
+     */
+    public void execSearchArticle() {
+        String regex = ui.getString("Keywords: ");
+        for (Article a : database.searchArticle(Pattern.compile(regex))) {
+            ui.putStringln(a.toString());
+        }
+    }
+    
+    /**
+     * Command: show detailed data about an article
+     * @throws InputRequiredException
+     * @throws ItemNotFoundException 
+     */
+    public void execShowArticle() throws InputRequiredException, ItemNotFoundException {
+        Article a = ui.getArticle();
+        ui.putStringln(a.toString());
+        if (a.getDescription() != null) {
+            ui.putStringln(a.getDescription());
+        }
+        File multimedia = a.getMultimedia();
+        if (multimedia != null) {
+            ui.putStringln("Multimedia: " + multimedia.getPath());
+        }
+        if (user != null && user.isAdmin()) {
+            ui.putStringln("User: " + a.getOwner().toString(true));
+        }
+    }
+    
+    /**
+     * Command: add a category
+     * @throws DuplicateEntryException
+     * @throws InputRequiredException
+     * @throws com.camilstaps.shop.Shell.AdminRequiredException
+     * @throws ItemNotFoundException 
+     */
+    public void execAddCategory() throws DuplicateEntryException, InputRequiredException, AdminRequiredException, ItemNotFoundException {
+        requireAdmin();
+        
+        String name = ui.getRequiredString("Name: ");
+        database.addItem(new Category(name));
+    }
+    
+    /**
+     * Command: list categories
+     */
+    public void execListCategories() {
+        for (String c : database.getCategoryNames()) {
+            ui.putStringln(c);
+        }
+    }
+    
+    /**
+     * Command: list users
+     * Administrators see a more detailed list
+     */
+    public void execListUsers() {
+        for (User u : database.getUsers()) {
+            ui.putStringln(u.toString(user != null && user.isAdmin()));
+        }
+    }
+    
+    /**
+     * Command: register a new user
+     * @throws DuplicateEntryException
+     * @throws InputRequiredException 
+     */
+    public void execRegister() throws DuplicateEntryException, InputRequiredException {
+        boolean addAsAdmin = false;
+        
+        if (database.getUsers().isEmpty()) {
+            addAsAdmin = true;
+            ui.putStringln("This is the first user and will therefore be added as administrator.");
+        } else if (user != null && user.isAdmin()) {
+            addAsAdmin = ui.getBoolean("Add user as administrator");
+        }
+        
+        String nr = ui.getRequiredString("Number: ");
+        String email = ui.getRequiredString("Email: ");
+        
+        User u = new User(nr, email, addAsAdmin);
+        
+        String password = u.setRandomPassword();
+        ui.putStringln("Password: " + password);
+        
+        database.addItem(u);
+    }
+    
+    /**
+     * Command: login
+     * @throws InputRequiredException
+     * @throws ItemNotFoundException 
+     */
+    public void execLogin() throws InputRequiredException, ItemNotFoundException {
+        if (user != null) {
+            ui.putStringln("You are already logged in.");
+            return;
+        }
+        
+        User u = ui.getUser();
+        String pw = ui.getRequiredString("Password: ");
+        
+        if (!u.verify(pw)) {
+            ui.putStringln("Failed to login.");
+            return;
+        }
+        
+        if (u.isBlocked()) {
+            ui.putStringln("You are blocked.");
+            return;
+        }
+        
+        user = u;
+    }
+    
+    /**
+     * Command: logout
+     */
+    public void execLogout() {
+        user = null;
+    }
+    
+    /**
+     * Command: add an article to the cart
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws ItemNotFoundException
+     * @throws InputRequiredException 
+     */
+    public void execAddToCart() throws LoginRequiredException, ItemNotFoundException, InputRequiredException {
+        requireLogin();
+        
+        user.getCart().add(ui.getArticle());
+    }
+    
+    /**
+     * Command: remove an article from the cart
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws ItemNotFoundException 
+     */
+    public void execRemoveFromCart() throws LoginRequiredException, ItemNotFoundException {
+        requireLogin();
+        
+        user.getCart().remove(ui.getArticle(user.getCart().getArticles()));
+    }
+    
+    /**
+     * Command: list articles in the cart
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws ItemNotFoundException 
+     */
+    public void execListCart() throws LoginRequiredException, ItemNotFoundException {
+        requireLogin();
+        
+        for (Article a : user.getCart().getArticles()) {
+            ui.putStringln(a.toString());
+        }
+        
+        ui.putStringln("Total value: " + user.getCart().getTotalAmount());
+    }
+    
+    /**
+     * Command: remove all articles from the cart
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws ItemNotFoundException 
+     */
+    public void execClearCart() throws LoginRequiredException, ItemNotFoundException {
+        requireLogin();
+        
+        if (ui.getBoolean("Are you sure?")) user.getCart().reset();
+    }
+    
+    /**
+     * Command: checkout (create an Order using the current Cart)
+     * @throws ItemNotFoundException
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws DuplicateEntryException 
+     */
+    public void execCheckout() throws ItemNotFoundException, LoginRequiredException, DuplicateEntryException {
+        requireLogin();
+        
+        if (user.getCart().getArticles().isEmpty()) {
+            throw new ItemNotFoundException();
+        }
+        
+        ui.putStringln("By checking out, you agree to pay the total amount.");
+        if (!ui.getBoolean("Do you agree?"))
+            return;
+        
+        Order order = new Order(user);
+        database.addItem(order);
+        
+        ui.putStringln("Your order has been added as " + order.toString());
+    }
+    
+    /**
+     * Command: list orders
+     * @throws ItemNotFoundException
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException 
+     */
+    public void execListOrders() throws ItemNotFoundException, LoginRequiredException {
+        requireLogin();
+        
+        Set<Order> orders;
+        if (user.isAdmin()) {
+            orders = database.getOrders();
+        } else {
+            orders = user.getOrders();
+        }
+        for (Order o : orders) {
+            ui.putStringln(o.toString());
+        }
+    }
+    
+    /**
+     * Command: show detailed information about an order
+     * @throws com.camilstaps.shop.Shell.LoginRequiredException
+     * @throws ItemNotFoundException
+     * @throws InputRequiredException 
+     */
+    public void execShowOrder() throws LoginRequiredException, ItemNotFoundException, InputRequiredException {
+        requireLogin();
+        
+        Order o;
+        if (user.isAdmin()) {
+            o = ui.getOrder();
+        } else {
+            o = ui.getOrder(user);
+        }
+        ui.putStringln(o.toString());
+        for (Article a : o.getArticles()) {
+            ui.putStringln("  " + a.toString());
+        }
+        ui.putStringln("Total amount: " + o.getTotalAmount());
+        ui.putStringln("Paid: " + (o.isPaid() ? "yes" : "no"));
+    }
+    
+    /**
+     * Command: set the paid status of an Order to true
+     * @throws com.camilstaps.shop.Shell.AdminRequiredException
+     * @throws ItemNotFoundException
+     * @throws InputRequiredException 
+     */
+    public void execSetOrderPaid() throws AdminRequiredException, ItemNotFoundException, InputRequiredException {
+        requireAdmin();
+        ui.getOrder().setPaid(true);
+    }
+    
+    /**
+     * Command: block a user
+     * @throws InputRequiredException
+     * @throws ItemNotFoundException
+     * @throws com.camilstaps.shop.Shell.AdminRequiredException 
+     */
+    public void execBlockUser() throws InputRequiredException, ItemNotFoundException, AdminRequiredException {
+        requireAdmin();
+        ui.getUser().setBlocked(true);
+    }
+    
+    /**
+     * Command: unblock a user
+     * @throws InputRequiredException
+     * @throws ItemNotFoundException
+     * @throws com.camilstaps.shop.Shell.AdminRequiredException 
+     */
+    public void execUnblockUser() throws InputRequiredException, ItemNotFoundException, AdminRequiredException {
+        requireAdmin();
+        ui.getUser().setBlocked(false);
+    }
+    
+    /**
+     * Command: save the database
+     */
+    public void execExit() {
+        database.write();
+    }
+    
+    /**
+     * This Exception is thrown when the visitor is required to login, but fails
+     */
+    private class LoginRequiredException extends Exception {
+    }
+    
+    /**
+     * This Exception is thrown when the visitor is required to login as an administrator, but fails
+     */
+    private class AdminRequiredException extends Exception {
+    }
+    
+}
diff --git a/Week9 Webshop/src/com/camilstaps/shop/Shop.java b/Week9 Webshop/src/com/camilstaps/shop/Shop.java
new file mode 100644
index 0000000..cab828a
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/Shop.java
@@ -0,0 +1,23 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+/**
+ * The webshop
+ * @author Camil Staps, s4498062
+ */
+public class Shop {
+    
+    /**
+     * Create a shell and run
+     * @param args 
+     */
+    public static void main(String[] args) {
+        Shell sh = new Shell(new CLIInteraction());
+        sh.run();
+    }
+    
+}
diff --git a/Week9 Webshop/src/com/camilstaps/shop/User.java b/Week9 Webshop/src/com/camilstaps/shop/User.java
new file mode 100644
index 0000000..12cfd4d
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/User.java
@@ -0,0 +1,143 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+import java.util.HashSet;
+import java.util.Random;
+import java.util.Set;
+
+/**
+ * A User is a person with a U/S-number, email and password.
+ * He may be blocked / be an admin, and has a Cart.
+ * @author Camil Staps, s4498062
+ */
+public class User extends DatabaseItem {
+
+    private final String nr;
+    private final String email;
+    private String hash;
+    private final boolean isAdmin;
+    private final Cart cart = new Cart();
+    private boolean isBlocked = false;
+
+    public User (String nr, String email) {
+        this.nr = nr;
+        this.email = email;
+        this.isAdmin = false;
+    }
+    
+    public User (String nr, String email, boolean isAdmin) {
+        this.nr = nr;
+        this.email = email;
+        this.isAdmin = isAdmin;
+    }
+    
+    public String getNr() {
+        return nr;
+    }
+    
+    public String getEmail() {
+        return email;
+    }
+    
+    public boolean isAdmin() {
+        return isAdmin;
+    }
+    
+    public Cart getCart() {
+        return cart;
+    }
+    
+    public void setBlocked(boolean set) {
+        isBlocked = set;
+    }
+    
+    public boolean isBlocked() {
+        return isBlocked;
+    }
+    
+    public Set<Article> getArticles() {
+        Set<Article> articles = Database.getInstance().getArticles();
+        Set<Article> result = new HashSet<>();
+        for (Article a : articles) {
+            if (a.getOwner().getNr().equals(nr)) {
+                result.add(a);
+            }
+        }
+        return result;
+    }
+    
+    public Set<Order> getOrders() {
+        Set<Order> orders = Database.getInstance().getOrders();
+        Set<Order> result = new HashSet<>();
+        for (Order o : orders) {
+            if (o.getUser().getNr().equals(nr)) {
+                result.add(o);
+            }
+        }
+        return result;
+    }
+    
+    /**
+     * Set a random new password for the user
+     * @return the new password
+     */
+    public String setRandomPassword() {
+        String pw = generatePassword();
+        hash = hash(pw);
+        return pw;
+    }
+
+    /**
+     * Hash a password. Currently, this is just the identity function.
+     * @param password
+     * @return 
+     */
+    public static String hash(String password) {
+        return password;
+    }
+    
+    /**
+     * Generate a random password
+     * @return 
+     */
+    private static String generatePassword() {
+        // Only characters that cannot easily be confused
+        final String drawFrom = "123456789abcdefghijkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ";
+        final Random r = new Random();
+        
+        StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < 12; i++) {
+            sb.append(drawFrom.charAt(r.nextInt(drawFrom.length())));
+        }
+        
+        return sb.toString();
+    }
+    
+    /**
+     * Verify if a password matches the user's password
+     * @param password the password to check
+     * @return 
+     */
+    public boolean verify(String password) {
+        return hash(password).equals(hash);
+    }
+    
+    @Override
+    public String toString() {
+        return (isAdmin ? "++ " : "") + nr + " (" + email + ")" + (isBlocked ? " -!-" : "");
+    }
+    
+    /**
+     * This User as a String, with a detailed and a quick view
+     * @param showSensitive whether to show sensitive data (email, isAdmin, isBlocked) or not
+     * @return 
+     */
+    public String toString(boolean showSensitive) {
+        return showSensitive ? toString() : nr;
+    }
+
+}
\ No newline at end of file
diff --git a/Week9 Webshop/src/com/camilstaps/shop/UserInteraction.java b/Week9 Webshop/src/com/camilstaps/shop/UserInteraction.java
new file mode 100644
index 0000000..1140089
--- /dev/null
+++ b/Week9 Webshop/src/com/camilstaps/shop/UserInteraction.java
@@ -0,0 +1,198 @@
+/**
+ * Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
+ * See the LICENSE file for copying permission.
+ */
+
+package com.camilstaps.shop;
+
+import java.util.Set;
+
+/**
+ * Interact with the user: provide and request information.
+ * @author Camil Staps, s4498062
+ */
+public abstract class UserInteraction {
+    
+    /**
+     * Show a String
+     * @param string 
+     */
+    abstract void putString(String string);
+    
+    /**
+     * Show a String with a linefeed
+     * @param string 
+     */
+    void putStringln(String string) {
+        putString(string + System.lineSeparator());
+    }
+    
+    /**
+     * Get a String as input
+     * @return 
+     */
+    abstract String getString();
+    
+    /**
+     * Get a String as input, after outputting a question
+     * @param question
+     * @return 
+     */
+    String getString(String question) {
+        putString(question);
+        return getString();
+    }
+    
+    /**
+     * Get a String as input, and throw an Exception when it's empty
+     * @return
+     * @throws InputRequiredException 
+     */
+    String getRequiredString() throws InputRequiredException {
+        String result = getString();
+        if (result.isEmpty()) throw new InputRequiredException();
+        return result;
+    }
+    
+    /**
+     * Get a String as input, after outputting a question, and throw an 
+     * Exception when the input is empty
+     * @param question
+     * @return
+     * @throws InputRequiredException 
+     */
+    String getRequiredString(String question) throws InputRequiredException {
+        putString(question);
+        return getRequiredString();
+    }
+    
+    /**
+     * Get a float as input
+     * @return 
+     */
+    abstract float getFloat();
+    
+    /**
+     * Get a float as input, after outputting a question
+     * @param question
+     * @return 
+     */
+    float getFloat(String question) {
+        putString(question);
+        return getFloat();
+    }
+    
+    /**
+     * Get a boolean as input
+     * @return 
+     */
+    abstract boolean getBoolean();
+    
+    /**
+     * Get a boolean as input, after outputting a question
+     * @param question
+     * @return 
+     */
+    boolean getBoolean(String question) {
+        putString(question);
+        return getBoolean();
+    }
+    
+    /**
+     * Get a Command as input
+     * @return 
+     */
+    abstract Command getCommand();
+
+    /**
+     * Let the user choose from an array of options, after outputting a question
+     * @param question
+     * @param options
+     * @return the index of the choice in the options array
+     */
+    abstract int getChoice(String question, String[] options);
+    
+    /**
+     * Let the user choose from a Set of Articles
+     * @param set
+     * @return 
+     */
+    Article getArticle(Set<Article> set) {
+        String[] articleNames = new String[set.size()];
+        Article[] articles = new Article[set.size()];
+        int i = 0;
+        for (Article a : set) {
+            articleNames[i] = a.toString();
+            articles[i++] = a;
+        }
+        return articles[getChoice("Article: ", articleNames)];
+    }
+    
+    /**
+     * Let the user choose an Article
+     * @return
+     * @throws InputRequiredException
+     * @throws ItemNotFoundException 
+     */
+    Article getArticle() throws InputRequiredException, ItemNotFoundException {
+        String name = getRequiredString("Name article: ");
+        return Database.getInstance().getArticle(name);
+    }
+    
+    /**
+     * Let the user choose an Article from the Articles of a specific User
+     * @param user
+     * @return 
+     */
+    Article getArticle(User user) {
+        return getArticle(user.getArticles());
+    }
+    
+    /**
+     * Let the user choose a category
+     * @return
+     * @throws ItemNotFoundException 
+     */
+    Category getCategory() throws ItemNotFoundException {
+        String[] categories = Database.getInstance().getCategoryNames();
+        return Database.getInstance().getCategory(categories[getChoice("Category: ", categories)]);
+    }
+    
+    /**
+     * Let the user choose a User
+     * @return
+     * @throws InputRequiredException
+     * @throws ItemNotFoundException 
+     */
+    User getUser() throws InputRequiredException, ItemNotFoundException {
+        return Database.getInstance().getUser(getRequiredString("Number user: "));
+    }
+    
+    /**
+     * Let the user choose an order
+     * @return
+     * @throws InputRequiredException
+     * @throws ItemNotFoundException 
+     */
+    Order getOrder() throws InputRequiredException, ItemNotFoundException {
+        return getOrder(getUser());
+    }
+    
+    /**
+     * Let the user choose an order, from the orders of a specific User
+     * @param user
+     * @return 
+     */
+    Order getOrder(User user) {
+        Set<Order> orders = user.getOrders();
+        String[] orderStrings = new String[orders.size()];
+        Order[] orderObjects = new Order[orders.size()];
+        int i = 0;
+        for (Order o : orders) {
+            orderStrings[i] = o.toString();
+            orderObjects[i++] = o;
+        }
+        return orderObjects[getChoice("Order: ", orderStrings)];
+    }
+
+}
\ No newline at end of file