samples: adds LCI samples (#1251)

* feat: add support for instance processing units

* docs: add sample for instance processing units

* fix: remove commented code + use junit asserts

* fix: remove Spanner snapshot reference

* test: add tests for InstanceInfo

* cleanup: fix formatting + tests

* chore: fix formatting

* test: fixes instanceinfo test

Due to master merge the compilation was failing. Fixes the builder
construction here.

* refactor: adds default impl for processing units

Adds default implementation for the InstanceInfo set processing units in
order to avoid a breaking change.

* samples: remove LCI samples for now

Removes the LCI samples for now, because they won't compile. We will
re-add them once the main implementation is released.

* Revert "samples: remove LCI samples for now"

This reverts commit dc17892.

* samples: fixes processing units samples for lci

Co-authored-by: Olav Loite <[email protected]>

Author: thiagotnunes

samples/snippets/src/main/java/com/example/spanner/CreateInstanceWithProcessingUnitsExample.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2021 Google LLC
+ *
+ * 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.spanner;
+
+//[START spanner_create_instance_with_processing_units]
+import com.google.api.gax.longrunning.OperationFuture;
+import com.google.cloud.spanner.Instance;
+import com.google.cloud.spanner.InstanceAdminClient;
+import com.google.cloud.spanner.InstanceConfigId;
+import com.google.cloud.spanner.InstanceId;
+import com.google.cloud.spanner.InstanceInfo;
+import com.google.cloud.spanner.Spanner;
+import com.google.cloud.spanner.SpannerOptions;
+import com.google.spanner.admin.instance.v1.CreateInstanceMetadata;
+import java.util.concurrent.ExecutionException;
+
+class CreateInstanceWithProcessingUnitsExample {
+
+  static void createInstance() {
+    // TODO(developer): Replace these variables before running the sample.
+    String projectId = "my-project";
+    String instanceId = "my-instance";
+    createInstance(projectId, instanceId);
+  }
+
+  static void createInstance(String projectId, String instanceId) {
+    Spanner spanner = SpannerOptions.newBuilder().setProjectId(projectId).build().getService();
+    InstanceAdminClient instanceAdminClient = spanner.getInstanceAdminClient();
+
+    // Set Instance configuration.
+    String configId = "regional-us-central1";
+    // This will create an instance with the processing power of 0.2 nodes.
+    int processingUnits = 500;
+    String displayName = "Descriptive name";
+
+    // Create an InstanceInfo object that will be used to create the instance.
+    InstanceInfo instanceInfo =
+        InstanceInfo.newBuilder(InstanceId.of(projectId, instanceId))
+            .setInstanceConfigId(InstanceConfigId.of(projectId, configId))
+            .setProcessingUnits(processingUnits)
+            .setDisplayName(displayName)
+            .build();
+    OperationFuture<Instance, CreateInstanceMetadata> operation =
+        instanceAdminClient.createInstance(instanceInfo);
+    try {
+      // Wait for the createInstance operation to finish.
+      Instance instance = operation.get();
+      System.out.printf("Instance %s was successfully created with %d processing units%n",
+          instance.getId(), instance.getProcessingUnits());
+    } catch (ExecutionException e) {
+      System.out.printf(
+          "Error: Creating instance %s failed with error message %s%n",
+          instanceInfo.getId(), e.getMessage());
+    } catch (InterruptedException e) {
+      System.out.println("Error: Waiting for createInstance operation to finish was interrupted");
+    }
+    spanner.close();
+  }
+}
+//[END spanner_create_instance_with_processing_units]