docs: add Multi Region Encryption samples

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

@@ -0,0 +1,106 @@
+/*
+ * Copyright 2024 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_database_with_MR_CMEK]
+
+import com.google.cloud.spanner.Spanner;
+import com.google.cloud.spanner.SpannerExceptionFactory;
+import com.google.cloud.spanner.SpannerOptions;
+import com.google.cloud.spanner.admin.database.v1.DatabaseAdminClient;
+import com.google.common.collect.ImmutableList;
+import com.google.spanner.admin.database.v1.CreateDatabaseRequest;
+import com.google.spanner.admin.database.v1.Database;
+import com.google.spanner.admin.database.v1.EncryptionConfig;
+import com.google.spanner.admin.database.v1.InstanceName;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+public class CreateDatabaseWithMultiRegionEncryptionKey {
+
+  static void createDatabaseWithEncryptionKey() {
+    // TODO(developer): Replace these variables before running the sample.
+    String projectId = "my-project";
+    String instanceId = "my-instance";
+    String databaseId = "my-database";
+    String[] kmsKeyNames =
+        new String[] {
+          "projects/" + projectId + "/locations/<location1>/keyRings/<keyRing>/cryptoKeys/<keyId>",
+          "projects/" + projectId + "/locations/<location2>/keyRings/<keyRing>/cryptoKeys/<keyId>",
+          "projects/" + projectId + "/locations/<location3>/keyRings/<keyRing>/cryptoKeys/<keyId>"
+        };
+    try (Spanner spanner =
+            SpannerOptions.newBuilder().setProjectId(projectId).build().getService();
+        DatabaseAdminClient adminClient = spanner.createDatabaseAdminClient()) {
+      createDatabaseWithMultiRegionEncryptionKey(
+          adminClient, projectId, instanceId, databaseId, kmsKeyNames);
+    }
+  }
+
+  static void createDatabaseWithMultiRegionEncryptionKey(
+      DatabaseAdminClient adminClient,
+      String projectId,
+      String instanceId,
+      String databaseId,
+      String[] kmsKeyNames) {
+    InstanceName instanceName = InstanceName.of(projectId, instanceId);
+    CreateDatabaseRequest request =
+        CreateDatabaseRequest.newBuilder()
+            .setParent(instanceName.toString())
+            .setCreateStatement("CREATE DATABASE `" + databaseId + "`")
+            .setEncryptionConfig(
+                EncryptionConfig.newBuilder()
+                    .addAllKmsKeyNames(ImmutableList.copyOf(kmsKeyNames))
+                    .build())
+            .addAllExtraStatements(
+                ImmutableList.of(
+                    "CREATE TABLE Singers ("
+                        + "  SingerId   INT64 NOT NULL,"
+                        + "  FirstName  STRING(1024),"
+                        + "  LastName   STRING(1024),"
+                        + "  SingerInfo BYTES(MAX)"
+                        + ") PRIMARY KEY (SingerId)",
+                    "CREATE TABLE Albums ("
+                        + "  SingerId     INT64 NOT NULL,"
+                        + "  AlbumId      INT64 NOT NULL,"
+                        + "  AlbumTitle   STRING(MAX)"
+                        + ") PRIMARY KEY (SingerId, AlbumId),"
+                        + "  INTERLEAVE IN PARENT Singers ON DELETE CASCADE"))
+            .build();
+    try {
+      System.out.println("Waiting for operation to complete...");
+      Database createdDatabase =
+          adminClient.createDatabaseAsync(request).get(120, TimeUnit.SECONDS);
+
+      System.out.printf(
+          "Database %s created with encryption keys %s%n",
+          createdDatabase.getName(), createdDatabase.getEncryptionConfig().getKmsKeyNamesList());
+    } catch (ExecutionException e) {
+      // If the operation failed during execution, expose the cause.
+      throw SpannerExceptionFactory.asSpannerException(e.getCause());
+    } catch (InterruptedException e) {
+      // Throw when a thread is waiting, sleeping, or otherwise occupied,
+      // and the thread is interrupted, either before or during the activity.
+      throw SpannerExceptionFactory.propagateInterrupt(e);
+    } catch (TimeoutException e) {
+      // If the operation timed out propagates the timeout
+      throw SpannerExceptionFactory.propagateTimeout(e);
+    }
+  }
+}
+// [END spanner_create_database_with_MR_CMEK]