public Builder clearEncryptionKey() {
      bitField0_ = (bitField0_ & ~0x00008000);
      encryptionKey_ = null;
      if (encryptionKeyBuilder_ != null) {
        encryptionKeyBuilder_.dispose();
        encryptionKeyBuilder_ = null;
      }
      onChanged();
      return this;
    }
<pre>
Immutable. Encrypts resources of this workstation configuration using a
customer-managed encryption key (CMEK).

If specified, the boot disk of the Compute Engine instance and the
persistent disk are encrypted using this encryption key. If
this field is not set, the disks are encrypted using a generated
key. Customer-managed encryption keys do not protect disk metadata.

If the customer-managed encryption key is rotated, when the workstation
instance is stopped, the system attempts to recreate the
persistent disk with the new version of the key. Be sure to keep
older versions of the key until the persistent disk is recreated.
Otherwise, data on the persistent disk might be lost.

If the encryption key is revoked, the workstation session automatically
stops within 7 hours.

Immutable after the workstation configuration is created.
</pre>

<code>
.google.cloud.workstations.v1.WorkstationConfig.CustomerEncryptionKey encryption_key = 17 [(.google.api.field_behavior) = IMMUTABLE];
</code>
java-workstations/proto-google-cloud-workstations-v1/src/main/java/com/google/cloud/workstations/v1/WorkstationConfig.java