@java.lang.Override
  public java.lang.String getDomain() {
    java.lang.Object ref = domain_;
    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();
      domain_ = s;
      return s;
    }
  }
<pre>
Required if
[allow_missing_ids][google.cloud.talent.v4beta1.RequestMetadata.allow_missing_ids]
is unset or `false`.

The client-defined scope or source of the service call, which typically
is the domain on
which the service has been implemented and is currently being run.

For example, if the service is being run by client &lt;em&gt;Foo, Inc.&lt;/em&gt;, on
job board www.foo.com and career site www.bar.com, then this field is
set to "foo.com" for use on the job board, and "bar.com" for use on the
career site.

Note that any improvements to the model for a particular tenant site rely
on this field being set correctly to a unique domain.

The maximum number of allowed characters is 255.
</pre>

<code>string domain = 1;</code>

@return The domain.
java-talent/proto-google-cloud-talent-v4beta1/src/main/java/com/google/cloud/talent/v4beta1/RequestMetadata.java