@java.lang.Override
  public java.lang.String getSubnetwork() {
    java.lang.Object ref = subnetwork_;
    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();
      subnetwork_ = s;
      return s;
    }
  }
<pre>
Immutable. Name of the Compute Engine subnetwork in which instances
associated with this workstation cluster will be created. Must be part of
the subnetwork specified for this workstation cluster.
</pre>

<code>string subnetwork = 11 [(.google.api.field_behavior) = IMMUTABLE];</code>

@return The subnetwork.
java-workstations/proto-google-cloud-workstations-v1/src/main/java/com/google/cloud/workstations/v1/WorkstationCluster.java