feat: Add additional Firestore query snippets (#1790)

* firestore sample for multiple inequality

* fix typo

* format code

* change samples to be in own file

* Create maven.yml

* Delete .github/workflows/maven.yml

* change query to lowercase to pass  test case

* fix checkstyle lint error

* update copyright dates

samples/snippets/src/main/java/com/example/firestore/snippets/MultipleRangeInequalityFiltersSnippets.java

@@ -0,0 +1,150 @@
+/*
+ * Copyright 2024 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.firestore.snippets;
+
+import com.example.firestore.snippets.model.City;
+import com.google.api.core.ApiFuture;
+import com.google.api.core.ApiFutures;
+import com.google.cloud.firestore.CollectionReference;
+import com.google.cloud.firestore.DocumentSnapshot;
+import com.google.cloud.firestore.Firestore;
+import com.google.cloud.firestore.Query;
+import com.google.cloud.firestore.Query.Direction;
+import com.google.cloud.firestore.QueryDocumentSnapshot;
+import com.google.cloud.firestore.QuerySnapshot;
+import com.google.cloud.firestore.WriteResult;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+/**
+ * Snippets to support firestore querying data documentation.
+ */
+class MultipleRangeInequalityFiltersSnippets {
+
+  private final Firestore db;
+
+  MultipleRangeInequalityFiltersSnippets(Firestore db) {
+    this.db = db;
+  }
+
+  /**
+   * Creates cities collection and add sample documents to test queries.
+   */
+  void prepareExamples() throws Exception {
+    // Data for each city
+    Map<String, Object> sfData = new HashMap<>();
+    sfData.put("name", "San Francisco");
+    sfData.put("state", "CA");
+    sfData.put("country", "USA");
+    sfData.put("capital", false);
+    sfData.put("population", 860000L);
+    sfData.put("density", 18000L);
+    sfData.put("regions", Arrays.asList("west_coast", "norcal"));
+
+    Map<String, Object> laData = new HashMap<>();
+    laData.put("name", "Los Angeles");
+    laData.put("state", "CA");
+    laData.put("country", "USA");
+    laData.put("capital", false);
+    laData.put("population", 3900000L);
+    laData.put("density", 8300L);
+    laData.put("regions", Arrays.asList("west_coast", "socal"));
+
+    Map<String, Object> dcData = new HashMap<>();
+    dcData.put("name", "Washington D.C.");
+    dcData.put("state", null);
+    dcData.put("country", "USA");
+    dcData.put("capital", true);
+    dcData.put("population", 680000L);
+    dcData.put("density", 11300L);
+    dcData.put("regions", Arrays.asList("east_coast"));
+
+    Map<String, Object> tokData = new HashMap<>();
+    tokData.put("name", "Tokyo");
+    tokData.put("state", null);
+    tokData.put("country", "Japan");
+    tokData.put("capital", true);
+    tokData.put("population", 9000000L);
+    tokData.put("density", 16000L);
+    tokData.put("regions", Arrays.asList("kanto", "honshu"));
+
+    Map<String, Object> bjData = new HashMap<>();
+    bjData.put("name", "Beijing");
+    bjData.put("state", null);
+    bjData.put("country", "China");
+    bjData.put("capital", true);
+    bjData.put("population", 21500000L);
+    bjData.put("density", 3500L);
+    bjData.put("regions", Arrays.asList("jingjinji", "hebei"));
+
+    CollectionReference citiesCollection = db.collection("cities");
+
+    // Add each city document
+    addCityDocument(citiesCollection, "SF", sfData);
+    addCityDocument(citiesCollection, "LA", laData);
+    addCityDocument(citiesCollection, "DC", dcData);
+    addCityDocument(citiesCollection, "TOK", tokData);
+    addCityDocument(citiesCollection, "BJ", bjData);
+
+    System.out.println("Data added successfully!");
+  }
+
+  private static void addCityDocument(CollectionReference citiesRef, String documentId,
+      Map<String, Object> data) {
+    ApiFuture<WriteResult> future = citiesRef.document(documentId).set(data);
+    try {
+      WriteResult result = future.get();
+      System.out.println("Update time : " + result.getUpdateTime());
+    } catch (Exception e) {
+      System.err.println("Error adding document: " + e.getMessage());
+    }
+  }
+
+  /* Example of Query with range and inequality filters. */
+  Query compoundMultiInequalities() {
+    // [START firestore_query_filter_compound_multi_ineq]
+    Query query = db.collection("cities")
+        .whereGreaterThan("population", 1000000)
+        .whereLessThan("density", 10000);
+    // [END firestore_query_filter_compound_multi_ineq]
+    return query;
+  }
+
+  /* Example of filtering indexes considering performance reasons. */
+  void indexingConsiderations() {
+    // [START firestore_query_indexing_considerations]
+    db.collection("employees")
+        .whereGreaterThan("salary", 100000)
+        .whereGreaterThan("experience", 0)
+        .orderBy("salary")
+        .orderBy("experience");
+    // [END firestore_query_indexing_considerations]
+  }
+
+  /**
+   * Closes the gRPC channels associated with this instance and frees up their resources.
+   */
+  void close() throws Exception {
+    db.close();
+  }
+}

samples/snippets/src/test/java/com/example/firestore/snippets/MultipleRangeInequalityFiltersSnippetsIT.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2024 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.firestore.snippets;
+
+import static com.google.common.collect.Sets.newHashSet;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import com.example.firestore.BaseIntegrationTest;
+import com.google.api.core.ApiFuture;
+import com.google.cloud.firestore.DocumentSnapshot;
+import com.google.cloud.firestore.Query;
+import com.google.cloud.firestore.QueryDocumentSnapshot;
+import com.google.cloud.firestore.QuerySnapshot;
+import com.google.common.collect.ImmutableMap;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+@SuppressWarnings("checkstyle:abbreviationaswordinname")
+public class MultipleRangeInequalityFiltersSnippetsIT extends BaseIntegrationTest {
+
+  private static MultipleRangeInequalityFiltersSnippets multipleRangeInequalityFiltersSnippets;
+
+  @BeforeClass
+  public static void setUpBeforeClass() throws Exception {
+    multipleRangeInequalityFiltersSnippets = new MultipleRangeInequalityFiltersSnippets(db);
+    multipleRangeInequalityFiltersSnippets.prepareExamples();
+  }
+
+  @Test
+  public void testRangeMultipleInequalityFilter() throws Exception {
+    Query query = multipleRangeInequalityFiltersSnippets.compoundMultiInequalities();
+
+    Set<String> expected = newHashSet("BJ", "LA");
+    Set<String> actual = getResultsAsSet(query);
+    assertEquals(expected, actual);
+  }
+
+  private Set<String> getResultsAsSet(Query query) throws Exception {
+    List<String> docIds = getResults(query);
+    return new HashSet<>(docIds);
+  }
+
+  private List<String> getResults(Query query) throws Exception {
+    // asynchronously retrieve query results
+    ApiFuture<QuerySnapshot> future = query.get();
+    // block on response
+    QuerySnapshot querySnapshot = future.get();
+
+    List<String> docIds = new ArrayList<>();
+    for (DocumentSnapshot document : querySnapshot.getDocuments()) {
+      docIds.add(document.getId());
+    }
+    return docIds;
+  }
+
+  @AfterClass
+  public static void tearDown() throws Exception {
+    deleteAllDocuments(db);
+    multipleRangeInequalityFiltersSnippets.close();
+  }
+}