#11 Rewrote, moved code to OrderManager

src/main/java/de/rwu/easydrop/PriceFetcher.java

@@ -1,96 +0,0 @@
-package de.rwu.easydrop;
-
-import java.net.MalformedURLException;
-import java.util.ArrayList;
-import java.util.List;
-
-import javax.naming.ConfigurationException;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.sqlite.SQLiteDataSource;
-
-import de.rwu.easydrop.api.client.DataSourceFactory;
-import de.rwu.easydrop.data.connector.AbstractProductPersistence;
-import de.rwu.easydrop.data.connector.SQLiteConnector;
-import de.rwu.easydrop.model.Product;
-import de.rwu.easydrop.model.ProductCatalogue;
-import de.rwu.easydrop.service.retriever.CatalogueRetriever;
-import de.rwu.easydrop.service.retriever.ProductRetriever;
-import de.rwu.easydrop.service.writer.CatalogueWriter;
-import de.rwu.easydrop.util.Config;
-import de.rwu.easydrop.util.ProductsConfig;
-
-
-/**
- * Diese Klasse PriceFetcher enthält die Methode getProductPrice, 
- * die den Preis eines Produkts von den jeweiligen API's abruft. 
- */
-public final class PriceFetcher {
-    static List<Double> api1Prices = new ArrayList<>();
-    static List<Double> api2Prices = new ArrayList<>();
-    
-    private static final Logger LOGGER = LoggerFactory.getLogger(PriceFetcher.class);
-
-    //Methode, um Preise der Prdukte zu vergleichen -> MArgen ermitteln
-    public static void comparePrices() throws ConfigurationException {
-    List<Double> api1Prices = new ArrayList<>();
-    List<Double> api2Prices = new ArrayList<>();
-
-    for (int i = 0; i < api1Prices.size(); i++) {
-        double api1Price = api1Prices.get(i);
-        double api2Price = api2Prices.get(i);
-        String productId = "Product " + (i + 1);
-
-        if (api1Price < api2Price) {
-            double priceDifference = api2Price - api1Price;
-            LOGGER.info("API 1 hat einen günstigeren Preis für " + productId +
-                    ". Der Preisunterschied beträgt: " + priceDifference);
-        } else if (api2Price < api1Price) {
-            double priceDifference = api1Price - api2Price;
-            LOGGER.info("API 2 hat einen günstigeren Preis für " + productId +
-                    ". Der Preisunterschied beträgt: " + priceDifference);
-        } else {
-            LOGGER.info("Beide APIs haben den gleichen Preis für " + productId);
-        }
-    }
-}
-
-    // Methode, um Preise der Produkte zu ermitteln
-    public static void getProductPrice(final String[] args) throws ConfigurationException{
-
-        Config config = Config.getInstance();
-        ProductsConfig pConfig = ProductsConfig.getInstance();
-        DataSourceFactory dataSourceFactory = new DataSourceFactory(config);
-        ProductRetriever retriever = new ProductRetriever(dataSourceFactory);
-        CatalogueRetriever catRetriever = new CatalogueRetriever(pConfig, retriever);
-        AbstractProductPersistence db = new SQLiteConnector(new SQLiteDataSource());
-        CatalogueWriter catWriter = new CatalogueWriter(db);
-
-        catRetriever.loadCatalogues();
-        List<ProductCatalogue> pCats = catRetriever.getProductCatalogues();
-        catWriter.writeCatalogues(pCats);
-
-        for (ProductCatalogue pCat : pCats) {
-            String pCatStr = pCat.toString();
-            LOGGER.info(pCatStr);
-        }
-
-        for (ProductCatalogue pCat : pCats) {
-        List<Product> products = pCat.getProducts();
-
-        for (Product product : products) {
-            String productId = product.getProductId();
-            double price = product.getCurrentPrice();
-            LOGGER.info("Product ID: " + productId + ", Price: " + price);
-            if (productId == "B096Y2TYKV") {
-                api1Prices.add(price);
-            } else if (productId == "Gigabyte GeForce RTX 3060") {
-                api2Prices.add(price);
-            }
-        }
-        }
-    }
-
-    
-}

src/main/java/de/rwu/easydrop/service/processing/OrderManager.java

@@ -1,10 +1,88 @@
 package de.rwu.easydrop.service.processing;
 
-/**
+import java.util.List;
- * Processes dropshipping orders.
- *
- * TODO implement
- */
-public class OrderManager {
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import de.rwu.easydrop.Main;
+import de.rwu.easydrop.exception.InvalidCatalogueException;
+import de.rwu.easydrop.model.Product;
+import de.rwu.easydrop.model.ProductCatalogue;
+import de.rwu.easydrop.model.ProductPair;
+import de.rwu.easydrop.util.FormattingUtil;
+
+/**
+ * Creates dropshipping orders based on price margin.
+ *
+ * @since 0.3.0
+ */
+public final class OrderManager {
+
+    /**
+     * Temporary logging instance.
+     */
+    private static final Logger LOGGER = LoggerFactory.getLogger(OrderManager.class);
+
+    /**
+     * Private constructor to prevent unwanted instantiation.
+     *
+     * @throws UnsupportedOperationException always
+     */
+    private OrderManager() throws UnsupportedOperationException {
+        throw new UnsupportedOperationException("This is a stateless class, don't instantiate it.");
+    }
+
+    /**
+     * Creates orders for products with sufficient margin.
+     *
+     * @param pCats Product Catalogues
+     */
+    public static void createOrders(final List<ProductCatalogue> pCats) {
+        for (ProductCatalogue pCat : pCats) {
+            ProductPair pair = getHighestMarginProducts(pCat);
+
+            // TODO: create actual orders/transactions, remove logger
+            double margin = pair.getProduct2().getCurrentPrice() -
+                    pair.getProduct1().getCurrentPrice();
+            String marginFormatted = FormattingUtil.formatEuro(margin);
+            LOGGER.info("{}: Margin {} ({} to {})",
+                    pCat.getProductName(),
+                    marginFormatted,
+                    pair.getProduct1().getDataOrigin(),
+                    pair.getProduct2().getDataOrigin());
+        }
+    }
+
+    /**
+     * Returns the cheapest and most expensive product of a catalogue to guarantee
+     * the biggest margin as a pair.
+     *
+     * @param pCat Product Catalogue
+     * @return Cheapest Product, Most Expensive Product as a Product Pair
+     */
+    public static ProductPair getHighestMarginProducts(final ProductCatalogue pCat) {
+        if (pCat.getProducts().size() < 2) {
+            throw new InvalidCatalogueException("Product Catalogue holds less than 2 products!");
+        }
+
+        // Initialize indexes
+        Product cheapestProduct = pCat.getProducts().get(0);
+        Product mostExpensiveProduct = pCat.getProducts().get(0);
+
+        for (Product product : pCat.getProducts()) {
+            if (product.getCurrentPrice() < cheapestProduct.getCurrentPrice()) {
+                cheapestProduct = product;
+            }
+            if (product.getCurrentPrice() > mostExpensiveProduct.getCurrentPrice()) {
+                mostExpensiveProduct = product;
+            }
+        }
+
+        if (cheapestProduct.getCurrentPrice() == mostExpensiveProduct.getCurrentPrice()) {
+            throw new InvalidCatalogueException("Price margin is zero!");
+        }
+
+        return new ProductPair(cheapestProduct, mostExpensiveProduct);
+    }
 }