public Builder clearPreferredLocation() {
      preferredLocation_ = getDefaultInstance().getPreferredLocation();
      bitField0_ = (bitField0_ & ~0x00000001);
      onChanged();
      return this;
    }
<pre>
Required. Zone that will remain operational when connection between the two
zones is lost. Specify the resource name of a zone that belongs to the
region of the private cloud. For example:
`projects/{project}/locations/europe-west3-a` where `{project}` can either
be a project number or a project ID.
</pre>

<code>
string preferred_location = 1 [(.google.api.field_behavior) = REQUIRED, (.google.api.resource_reference) = { ... }
</code>

@return This builder for chaining.
java-vmwareengine/proto-google-cloud-vmwareengine-v1/src/main/java/com/google/cloud/vmwareengine/v1/StretchedClusterConfig.java