diff --git a/google-cloud-clients/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerClient.java b/google-cloud-clients/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerClient.java
index 7543b54fccdc..8979209d9c6d 100644
--- a/google-cloud-clients/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerClient.java
+++ b/google-cloud-clients/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerClient.java
@@ -1399,10 +1399,10 @@ public final UnaryCallable<RollbackRequest, Empty> rollbackCallable() {
    *
    * <pre><code>
    * try (SpannerClient spannerClient = SpannerClient.create()) {
-   *   String formattedSession = SessionName.format("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]");
+   *   SessionName session = SessionName.of("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]");
    *   String sql = "";
    *   PartitionQueryRequest request = PartitionQueryRequest.newBuilder()
-   *     .setSession(formattedSession)
+   *     .setSession(session.toString())
    *     .setSql(sql)
    *     .build();
    *   PartitionResponse response = spannerClient.partitionQuery(request);
@@ -1433,10 +1433,10 @@ public final PartitionResponse partitionQuery(PartitionQueryRequest request) {
    *
    * <pre><code>
    * try (SpannerClient spannerClient = SpannerClient.create()) {
-   *   String formattedSession = SessionName.format("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]");
+   *   SessionName session = SessionName.of("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]");
    *   String sql = "";
    *   PartitionQueryRequest request = PartitionQueryRequest.newBuilder()
-   *     .setSession(formattedSession)
+   *     .setSession(session.toString())
    *     .setSql(sql)
    *     .build();
    *   ApiFuture&lt;PartitionResponse&gt; future = spannerClient.partitionQueryCallable().futureCall(request);
@@ -1467,11 +1467,11 @@ public final UnaryCallable<PartitionQueryRequest, PartitionResponse> partitionQu
    *
    * <pre><code>
    * try (SpannerClient spannerClient = SpannerClient.create()) {
-   *   String formattedSession = SessionName.format("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]");
+   *   SessionName session = SessionName.of("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]");
    *   String table = "";
    *   KeySet keySet = KeySet.newBuilder().build();
    *   PartitionReadRequest request = PartitionReadRequest.newBuilder()
-   *     .setSession(formattedSession)
+   *     .setSession(session.toString())
    *     .setTable(table)
    *     .setKeySet(keySet)
    *     .build();
@@ -1504,11 +1504,11 @@ public final PartitionResponse partitionRead(PartitionReadRequest request) {
    *
    * <pre><code>
    * try (SpannerClient spannerClient = SpannerClient.create()) {
-   *   String formattedSession = SessionName.format("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]");
+   *   SessionName session = SessionName.of("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]");
    *   String table = "";
    *   KeySet keySet = KeySet.newBuilder().build();
    *   PartitionReadRequest request = PartitionReadRequest.newBuilder()
-   *     .setSession(formattedSession)
+   *     .setSession(session.toString())
    *     .setTable(table)
    *     .setKeySet(keySet)
    *     .build();
diff --git a/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/admin/database/v1/MockDatabaseAdminImpl.java b/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/admin/database/v1/MockDatabaseAdminImpl.java
index 9f386abd9f18..adfc650e4cb3 100644
--- a/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/admin/database/v1/MockDatabaseAdminImpl.java
+++ b/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/admin/database/v1/MockDatabaseAdminImpl.java
@@ -43,7 +43,7 @@
 @javax.annotation.Generated("by GAPIC")
 @BetaApi
 public class MockDatabaseAdminImpl extends DatabaseAdminImplBase {
-  private ArrayList<AbstractMessage> requests;
+  private List<AbstractMessage> requests;
   private Queue<Object> responses;
 
   public MockDatabaseAdminImpl() {
diff --git a/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/admin/instance/v1/MockInstanceAdminImpl.java b/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/admin/instance/v1/MockInstanceAdminImpl.java
index 65e63c003099..2b45832fc956 100644
--- a/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/admin/instance/v1/MockInstanceAdminImpl.java
+++ b/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/admin/instance/v1/MockInstanceAdminImpl.java
@@ -45,7 +45,7 @@
 @javax.annotation.Generated("by GAPIC")
 @BetaApi
 public class MockInstanceAdminImpl extends InstanceAdminImplBase {
-  private ArrayList<AbstractMessage> requests;
+  private List<AbstractMessage> requests;
   private Queue<Object> responses;
 
   public MockInstanceAdminImpl() {
diff --git a/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/MockSpannerImpl.java b/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/MockSpannerImpl.java
index 344b248ef736..7a1465d9ac97 100644
--- a/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/MockSpannerImpl.java
+++ b/google-cloud-clients/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/MockSpannerImpl.java
@@ -48,7 +48,7 @@
 @javax.annotation.Generated("by GAPIC")
 @BetaApi
 public class MockSpannerImpl extends SpannerImplBase {
-  private ArrayList<AbstractMessage> requests;
+  private List<AbstractMessage> requests;
   private Queue<Object> responses;
 
   public MockSpannerImpl() {
diff --git a/google-cloud-clients/google-cloud-spanner/synth.metadata b/google-cloud-clients/google-cloud-spanner/synth.metadata
index 562c7c2b3190..503625f63432 100644
--- a/google-cloud-clients/google-cloud-spanner/synth.metadata
+++ b/google-cloud-clients/google-cloud-spanner/synth.metadata
@@ -1,19 +1,19 @@
 {
-  "updateTime": "2019-03-29T07:55:57.058527Z",
+  "updateTime": "2019-04-02T07:55:48.539500Z",
   "sources": [
     {
       "generator": {
         "name": "artman",
-        "version": "0.16.21",
-        "dockerImage": "googleapis/artman@sha256:854131ec1af7b3a313253474c24748dc0acd217a58a0b74dbfb559f340a15d78"
+        "version": "0.16.22",
+        "dockerImage": "googleapis/artman@sha256:e7f9554322a8aa1416c122c918fdc4cdec8cfe816f027fc948dec0be7edef320"
       }
     },
     {
       "git": {
         "name": "googleapis",
         "remote": "https://github.com/googleapis/googleapis.git",
-        "sha": "37386f1ebcaed51bcb7d15d00124d22c38606e45",
-        "internalRef": "240841842"
+        "sha": "6c48ab5aef47dc14e02e2dc718d232a28067129d",
+        "internalRef": "241437588"
       }
     }
   ],