public Builder clearClusterId() {
        clusterId_ = getDefaultInstance().getClusterId();
        bitField0_ = (bitField0_ & ~0x00000001);
        onChanged();
        return this;
      }
<pre>
Required. The user-provided identifier of the new `Cluster`.
The identifier must meet the following requirements:

* Only contains 1-63 alphanumeric characters and hyphens
* Begins with an alphabetical character
* Ends with a non-hyphen character
* Not formatted as a UUID
* Complies with [RFC
1034](https://datatracker.ietf.org/doc/html/rfc1034) (section 3.5)
</pre>

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

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