Update search algo

src/main/java/com/google/sps/data/Meal.java

@@ -15,6 +15,7 @@
 package com.google.sps.data;
 
 import java.util.ArrayList;
+import java.util.List;
 
 public class Meal {
     private final Long id;
@@ -50,4 +51,28 @@ public ArrayList<String> getIngredients() {
     public String getType() {
         return this.type;
     }
+
+    /**
+     * Counts the number of keywords that are matching in recipe.
+     * @param params list of strings with keywords, that describe search request.
+     * @return amount of occurrences of keywords from params in this meal.
+     */
+    public int getFrequency(List<String> params) {
+        int frequency = 0;
+        for (String param : params) {
+            if (title.contains(param) ||
+                description.contains(param) ||
+                type.contains(param)) {
+                frequency++;
+                continue;
+            } 
+            for (String ingredient : ingredients) {
+                if (ingredient.contains(param)) {
+                    frequency++;
+                    continue;
+                }
+            }
+        }
+        return frequency;
+    }
 }

src/main/java/com/google/sps/servlets/MealServlet.java

@@ -34,6 +34,7 @@
 import java.util.Collection;
 import java.util.List;
 import java.util.Random;
+import java.util.TreeMap;
 import java.util.stream.Collectors;
 import javax.servlet.annotation.WebServlet;
 import javax.servlet.http.HttpServlet;
@@ -97,9 +98,19 @@ private void getMealList(HttpServletRequest request, HttpServletResponse respons
         // Every object Meal adds if it contains at least one keyword in at least one field 
         // (type, title, description, ingredients).
         List<Meal> searchedMeal = new ArrayList<>();
+        TreeMap<Integer, List<Meal>> sortedMeal = new TreeMap<>();
         for (Meal meal : meals) {
-            if (isResultOfSearch(meal, params)) {
-                searchedMeal.add(meal);
+            int frequency = meal.getFrequency(params);
+            if (frequency > 0) {
+                sortedMeal.putIfAbsent(frequency, new ArrayList<>());
+                List<Meal> list = sortedMeal.get(frequency);
+                list.add(meal);
+            }
+        }
+        for (int key : sortedMeal.descendingKeySet()) {
+            List<Meal> list = sortedMeal.get(key);
+            if (list != null) {
+                searchedMeal.addAll(list);
             }
         }
         response.setContentType("application/json");
@@ -187,25 +198,6 @@ private Meal pickRandomMeal(List<Meal> mealList) {
         return (Meal)mealList.get(index);
     }
 
-    private Boolean isResultOfSearch(Meal meal, List<String> params) {
-        for (String param : params) {
-            if (meal.getTitle().contains(param)) {
-                return true;
-            } 
-            if (meal.getDescription().contains(param)) {
-                return true;
-            } 
-            if (meal.getType().contains(param)) {
-                return true;
-            }
-            for (String ingredient : meal.getIngredients()) {
-                if (ingredient.contains(param)) {
-                    return true;
-                }
-            }
-        }
-        return false;
-    }
     private String getParameter(HttpServletRequest request, String name, String defaultValue) {
         String value = request.getParameter(name);
         if (value == null) {

src/test/java/com/google/sps/MealServletTest.java

@@ -173,10 +173,11 @@ public void getMealListTest() throws IOException, ServletException {
 
     // Get a list of objects Meal from datastore by search request "potato onion".
     // (Check if meal that has both occurrences of searching keywords would be added only once).
-    // Expected result: a JSON String of list with one object MEAL_1.
+    // Expected result: a JSON String of list with objects in order: MEAL_1, PIZZA_2.
     @Test
     public void getMealListWithTwoKeyWordsTest() throws IOException, ServletException {
         DatastoreService ds = DatastoreServiceFactory.getDatastoreService();
+        ds.put(DataConverter.createMealEntity(PIZZA_2));
         ds.put(DataConverter.createMealEntity(MEAL_1));
         ds.put(DataConverter.createMealEntity(MEAL_2));
 
@@ -188,6 +189,7 @@ public void getMealListWithTwoKeyWordsTest() throws IOException, ServletExceptio
 
         List<Meal> meals = new ArrayList<>();
         meals.add(MEAL_1);
+        meals.add(PIZZA_2);
         Gson gson = new Gson();
         String expected = gson.toJson(meals);
         String actual = response.getContentAsString().trim();