chore: added regional endpoint sample for datastore

README.md

@@ -262,6 +262,7 @@ Samples are in the [`samples/`](https://github.com/googleapis/java-datastore/tre
 | --------------------------- | --------------------------------- | ------ |
 | Native Image Datastore Sample | [source code](https://github.com/googleapis/java-datastore/blob/main/samples/native-image-sample/src/main/java/com/example/datastore/NativeImageDatastoreSample.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-datastore&page=editor&open_in_editor=samples/native-image-sample/src/main/java/com/example/datastore/NativeImageDatastoreSample.java) |
 | Quickstart Sample | [source code](https://github.com/googleapis/java-datastore/blob/main/samples/snippets/src/main/java/com/example/datastore/QuickstartSample.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-datastore&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/datastore/QuickstartSample.java) |
+| Regional Endpoint | [source code](https://github.com/googleapis/java-datastore/blob/main/samples/snippets/src/main/java/com/example/datastore/RegionalEndpoint.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-datastore&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/datastore/RegionalEndpoint.java) |
 | Count Aggregation In Transaction | [source code](https://github.com/googleapis/java-datastore/blob/main/samples/snippets/src/main/java/com/example/datastore/aggregation/CountAggregationInTransaction.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-datastore&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/datastore/aggregation/CountAggregationInTransaction.java) |
 | Count Aggregation On Kind | [source code](https://github.com/googleapis/java-datastore/blob/main/samples/snippets/src/main/java/com/example/datastore/aggregation/CountAggregationOnKind.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-datastore&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/datastore/aggregation/CountAggregationOnKind.java) |
 | Count Aggregation With Gql Query | [source code](https://github.com/googleapis/java-datastore/blob/main/samples/snippets/src/main/java/com/example/datastore/aggregation/CountAggregationWithGqlQuery.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-datastore&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/datastore/aggregation/CountAggregationWithGqlQuery.java) |

samples/snippets/src/main/java/com/example/datastore/RegionalEndpoint.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2023 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.datastore;
+
+// Imports the Google Cloud client library
+// [START datastore_regional_endpoint]
+
+import com.google.cloud.datastore.Datastore;
+import com.google.cloud.datastore.DatastoreOptions;
+
+public class RegionalEndpoint {
+
+  public Datastore createClient() throws Exception {
+    // Instantiates a client
+    DatastoreOptions options =
+        DatastoreOptions.newBuilder().setHost("https://nam5-datastore.googleapis.com").build();
+    Datastore datastore = options.getService();
+    return datastore;
+  }
+}
+// [END datastore_regional_endpoint]

samples/snippets/src/test/java/com/example/datastore/RegionalEndpointIT.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2023 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.datastore;
+
+import static org.junit.Assert.assertEquals;
+
+import com.google.cloud.datastore.Datastore;
+import com.google.cloud.datastore.Entity;
+import com.google.cloud.datastore.Key;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/**
+ * Tests for quickstart sample.
+ */
+@RunWith(JUnit4.class)
+@SuppressWarnings("checkstyle:abbreviationaswordinname")
+public class RegionalEndpointIT {
+
+  private static RegionalEndpoint regionalEndpoint;
+
+  private static final void deleteTestEntity(Datastore datastore) {
+    String kind = "Task";
+    String name = "sampletask1";
+    Key taskKey = datastore.newKeyFactory().setKind(kind).newKey(name);
+    datastore.delete(taskKey);
+  }
+
+  @Before
+  public void setUp() {
+    regionalEndpoint = new RegionalEndpoint();
+  }
+
+  @Test
+  public void testRegionalEndpoint() throws Exception {
+    Datastore datastoreWithEndpoint = regionalEndpoint.createClient();
+
+    // run a few operations with the client
+    deleteTestEntity(datastoreWithEndpoint);
+    // The kind for the new entity
+    String kind = "Task";
+    // The name/ID for the new entity
+    String name = "regionalEndpointClient50720906";
+    // The Cloud Datastore key for the new entity
+    Key taskKey = datastoreWithEndpoint.newKeyFactory().setKind(kind).newKey(name);
+
+    // Prepares the new entity
+    Entity task = Entity.newBuilder(taskKey).set("description", "Buy milk").build();
+
+    // Saves the entity
+    datastoreWithEndpoint.put(task);
+
+    // Retrieve entity
+    Entity retrieved = datastoreWithEndpoint.get(taskKey);
+
+    assertEquals(task, retrieved);
+    deleteTestEntity(datastoreWithEndpoint);
+  }
+}