@java.lang.Override
      public java.lang.String getClientId() {
        java.lang.Object ref = clientId_;
        if (ref instanceof java.lang.String) {
          return (java.lang.String) ref;
        } else {
          com.google.protobuf.ByteString bs = (com.google.protobuf.ByteString) ref;
          java.lang.String s = bs.toStringUtf8();
          clientId_ = s;
          return s;
        }
      }
<pre>
Required. The client (application) ID of the application with federated
credentials.
</pre>

<code>string client_id = 1 [(.google.api.field_behavior) = REQUIRED];</code>

@return The clientId.
java-storage-transfer/proto-google-cloud-storage-transfer-v1/src/main/java/com/google/storagetransfer/v1/proto/TransferTypes.java