feat: add getter for universe domain in JwtCredentialsWithAudience

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/internal/JwtCredentialsWithAudience.java

@@ -76,4 +76,9 @@ public boolean hasRequestMetadataOnly() {
   public void refresh() throws IOException {
     delegate.refresh();
   }
+
+  @Override
+  public String getUniverseDomain() {
+    return delegate.getUniverseDomain();
+  }
 }

google-cloud-bigtable/src/test/java/com/google/cloud/bigtable/data/v2/JwtCredentialsWithAudienceTests.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2025 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
+ *
+ *     https://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.google.cloud.bigtable.data.v2;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.auth.oauth2.OAuth2Utils;
+import com.google.auth.oauth2.ServiceAccountJwtAccessCredentials;
+import com.google.cloud.bigtable.data.v2.internal.JwtCredentialsWithAudience;
+import java.io.IOException;
+import java.net.URI;
+import java.security.PrivateKey;
+import org.junit.Test;
+
+public class JwtCredentialsWithAudienceTests {
+
+  private static final String SA_CLIENT_EMAIL =
+      "36680232662-vrd7ji19qe3nelgchd0ah2csanun6bnr@developer.gserviceaccount.com";
+  private static final String SA_CLIENT_ID =
+      "36680232662-vrd7ji19qe3nelgchd0ah2csanun6bnr.apps.googleusercontent.com";
+  private static final String SA_PRIVATE_KEY_ID = "d84a4fefcf50791d4a90f2d7af17469d6282df9d";
+  private static final String SA_PRIVATE_KEY_PKCS8 =
+      "-----BEGIN PRIVATE KEY-----\n"
+          + "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\n"
+          + "-----END PRIVATE KEY-----\n";
+  private static final String QUOTA_PROJECT = "sample-quota-project-id";
+
+  @Test
+  public void getUniverseDomain_default() throws IOException {
+    PrivateKey privateKey = OAuth2Utils.privateKeyFromPkcs8(SA_PRIVATE_KEY_PKCS8);
+    ServiceAccountJwtAccessCredentials serviceAccountJwtAccessCredentials =
+        ServiceAccountJwtAccessCredentials.newBuilder()
+            .setClientId(SA_CLIENT_ID)
+            .setClientEmail(SA_CLIENT_EMAIL)
+            .setPrivateKey(privateKey)
+            .setPrivateKeyId(SA_PRIVATE_KEY_ID)
+            .setQuotaProjectId(QUOTA_PROJECT)
+            .build();
+    JwtCredentialsWithAudience jwtWithAudience =
+        new JwtCredentialsWithAudience(
+            serviceAccountJwtAccessCredentials, URI.create("default-aud"));
+    assertThat(jwtWithAudience.getUniverseDomain()).isEqualTo("googleapis.com");
+  }
+
+  @Test
+  public void getUniverseDomain_custom() throws IOException {
+    PrivateKey privateKey = OAuth2Utils.privateKeyFromPkcs8(SA_PRIVATE_KEY_PKCS8);
+    ServiceAccountJwtAccessCredentials serviceAccountJwtAccessCredentials =
+        ServiceAccountJwtAccessCredentials.newBuilder()
+            .setClientId(SA_CLIENT_ID)
+            .setClientEmail(SA_CLIENT_EMAIL)
+            .setPrivateKey(privateKey)
+            .setPrivateKeyId(SA_PRIVATE_KEY_ID)
+            .setQuotaProjectId(QUOTA_PROJECT)
+            .setUniverseDomain("example.com")
+            .build();
+    JwtCredentialsWithAudience jwtWithAudience =
+        new JwtCredentialsWithAudience(
+            serviceAccountJwtAccessCredentials, URI.create("default-aud"));
+    assertThat(jwtWithAudience.getUniverseDomain()).isEqualTo("example.com");
+  }
+}