hw4

build.gradle

@@ -12,6 +12,12 @@ repositories {
 sourceCompatibility = 10
 
 dependencies {
+    // https://mvnrepository.com/artifact/org.hsqldb/hsqldb
+    compile group: 'org.hsqldb', name: 'hsqldb', version: '2.4.1'
+
+    // https://mvnrepository.com/artifact/org.apache.commons/commons-dbcp2
+    compile group: 'org.apache.commons', name: 'commons-dbcp2', version: '2.5.0'
+
     // https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind
     compile group: 'com.fasterxml.jackson.core', name: 'jackson-databind', version: '2.9.7'
 

src/main/java/DAO/OrdersDao.java

@@ -0,0 +1,81 @@
+package DAO;
+
+import DTO.Order;
+import util.DataSourceProvider;
+
+import java.sql.*;
+import java.util.ArrayList;
+import java.util.List;
+
+public class OrdersDao {
+
+    static private int nextOrderId = 0;
+
+    public static Order getOrderForId(int id) {
+        Order order = new Order();
+        String sql = "select 'order_number' from ORDERS where id=?;";
+        try (Connection connection = DataSourceProvider.getDataSource().getConnection();
+             PreparedStatement ps = connection.prepareStatement(sql)) {
+            ps.setInt(1, id);
+            try (ResultSet rs = ps.executeQuery()) {
+                if (rs.next()) {
+                    order.setId(id);
+                    order.setOrderNumber(rs.getString("order_number"));
+                    return order;
+                }
+            }
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+        return null;
+    }
+    public static List<Order> getAllOrders() {
+        List<Order> orders = new ArrayList<Order>();
+        String sql = "select id, order_number from orders;";
+        try (Connection connection = DataSourceProvider.getDataSource().getConnection();
+             Statement statement = connection.createStatement() ){
+
+            try (ResultSet rs = statement.executeQuery(sql)) {
+                while(rs.next()) {
+                    Order order = new Order();
+                    order.setId(rs.getInt(1));
+                    order.setOrderNumber(rs.getString(2));
+                    orders.add(order);
+                }
+            }
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+
+        return orders;
+    }
+
+    public static void saveOrder(Order order) {
+        order.setId(nextOrderId++);
+        String sql = "insert into orders (id, order_number) values (?, ?);";
+        try (Connection connection = DataSourceProvider.getDataSource().getConnection();
+             PreparedStatement ps = connection.prepareStatement(sql)) {
+            ps.setInt(1, order.getId());
+            ps.setString(2, order.getOrderNumber());
+            ps.execute();
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public static int getCount() {
+        String sql = "select count(*) from orders;";
+        try (Connection connection = DataSourceProvider.getDataSource().getConnection();
+             Statement ps = connection.createStatement()) {
+            try (ResultSet rs = ps.executeQuery(sql)) {
+                if (rs.next()) {
+                    return rs.getInt(1);
+                }
+            }
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+        return 0;
+    }
+}

src/main/java/Startup.java

@@ -0,0 +1,39 @@
+import util.DataSourceProvider;
+
+import javax.servlet.ServletContextEvent;
+import javax.servlet.ServletContextListener;
+import javax.servlet.annotation.WebListener;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+import static util.FileUtil.readFileFromClasspath;
+
+@WebListener
+public class Startup implements ServletContextListener {
+
+    @Override
+    public void contextInitialized(ServletContextEvent sce) {
+        System.out.println("Set jdbc provider url");
+        DataSourceProvider.setDbUrl("jdbc:hsqldb:mem:shop.");
+
+        System.out.println("Load sql");
+        String sql = readFileFromClasspath("sql/schema.sql");
+
+        try (Connection connection = DataSourceProvider.getDataSource().getConnection();
+            Statement statement = connection.createStatement()) {
+
+            statement.execute(sql);
+
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+        System.out.println("Ready");
+    }
+
+    @Override
+    public void contextDestroyed(ServletContextEvent sce) {
+
+    }
+}

src/main/java/servlet/api/Orders.java

@@ -1,5 +1,6 @@
 package servlet.api;
 
+import DAO.OrdersDao;
 import DTO.Order;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
@@ -13,39 +14,30 @@ import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
 
 @WebServlet(urlPatterns = "/api/orders", name="Orders")
-@WebListener
-public class Orders extends HttpServlet implements ServletContextListener {
+public class Orders extends HttpServlet {
     private static final long serialVersionUID = 1L;
-    private static int nextOrderId = 0;
-    private static Map orders = new HashMap<Integer, Order>();
-
-    public int addOrder(Order order) {
-        int orderId = nextOrderId;
-        nextOrderId++;
-        order.setId(orderId);
-        orders.put(orderId, order);
-        return orderId;
-    }
 
     @Override
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        resp.setContentType("application/json");
         String idString = req.getParameter("id");
         if (idString != null) {
             int id = Integer.parseInt(idString);
-            Order order = (Order) orders.get(id);
+            Order order = OrdersDao.getOrderForId(id);
             if (order == null) {
                 resp.setStatus(404);
                 return;
             }
-            resp.setContentType("application/json");
             resp.getWriter().print(new ObjectMapper().writeValueAsString(order));
             return;
         }
-        resp.getWriter().format("%s %d", getServletName(), orders.size());
+        List<Order> orders = OrdersDao.getAllOrders();
+        resp.getWriter().print(new ObjectMapper().writeValueAsString(orders));
     }
 
     @Override
@@ -54,19 +46,8 @@ public class Orders extends HttpServlet implements ServletContextListener {
         String orderJson = req.getReader().lines().collect(Collectors.joining(" "));
 
         Order order = new ObjectMapper().readValue(orderJson, Order.class);
-        addOrder(order);
+        OrdersDao.saveOrder(order);
         resp.getWriter().print(new ObjectMapper().writeValueAsString(order));
 
     }
-
-    @Override
-    public void contextInitialized(ServletContextEvent sce) {
-        // fixme horrible hack
-        sce.getServletContext().setAttribute("Orders", this);
-    }
-
-    @Override
-    public void contextDestroyed(ServletContextEvent sce) {
-
-    }
 }

src/main/java/servlet/html/OrdersForm.java

@@ -1,5 +1,6 @@
 package servlet.html;
 
+import DAO.OrdersDao;
 import DTO.Order;
 import servlet.api.Orders;
 
@@ -29,12 +30,6 @@ public class OrdersForm extends HttpServlet
     @Override
     protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
         resp.setContentType("application/json");
-        // fixme horrible hack
-        Orders orders = (Orders) getServletContext().getAttribute("Orders");
-        if (orders == null) {
-            throw new NullPointerException("Orders servlet not found");
-        }
-
         String orderNumber = req.getParameter("orderNumber");
         if (orderNumber == null) {
             resp.setStatus(400, "orderNumber parameter is empty");
@@ -44,7 +39,7 @@ public class OrdersForm extends HttpServlet
 
         Order order = new Order();
         order.setOrderNumber(orderNumber);
-        int orderId = orders.addOrder(order);
-        resp.getWriter().format("%d", orderId);
+        OrdersDao.saveOrder(order);
+        resp.getWriter().format("%d", order.getId());
     }
 }

src/main/java/util/DataSourceProvider.java

@@ -0,0 +1,35 @@
+package util;
+
+import org.apache.commons.dbcp2.BasicDataSource;
+
+import javax.sql.DataSource;
+
+public class DataSourceProvider {
+
+    private static String dbUrl = null;
+
+    private static BasicDataSource dataSource = null;
+
+    public static void setDbUrl(String url) {
+        dbUrl = url;
+    }
+
+    public static DataSource getDataSource() {
+        if (dataSource != null) {
+            return dataSource;
+        }
+
+        if (dbUrl == null) {
+            throw new IllegalStateException(
+                    "Database url not configured. Use setDbUrl()");
+        }
+
+        dataSource = new BasicDataSource();
+        dataSource.setDriverClassName("org.hsqldb.jdbcDriver");
+        dataSource.setUrl(dbUrl);
+        dataSource.setMaxTotal(3);
+
+        return dataSource;
+    }
+
+}

src/main/resources/sql/schema.sql

@@ -0,0 +1,4 @@
+CREATE TABLE orders (
+id BIGINT NOT NULL PRIMARY KEY ,
+order_number VARCHAR (255)
+);