public Builder clearBootDiskConfig() {
      bitField0_ = (bitField0_ & ~0x04000000);
      bootDiskConfig_ = null;
      if (bootDiskConfigBuilder_ != null) {
        bootDiskConfigBuilder_.dispose();
        bootDiskConfigBuilder_ = null;
      }
      onChanged();
      return this;
    }
<pre>
Optional. Boot disk configuration.
</pre>

<code>
.google.cloud.tpu.v2alpha1.BootDiskConfig boot_disk_config = 49 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-tpu/proto-google-cloud-tpu-v2alpha1/src/main/java/com/google/cloud/tpu/v2alpha1/Node.java