@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(name_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 1, name_);
    }
    if (((bitField0_ & 0x00000001) != 0)) {
      output.writeMessage(2, getTtl());
    }
    if (((bitField0_ & 0x00000002) != 0)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 3, backupId_);
    }
    getUnknownFields().writeTo(output);
  }
<pre>
Optional. The id of the backup to be created. If not specified, the
default value ([YYYYMMDDHHMMSS]_[Shortened Instance UID] is used.
</pre>

<code>optional string backup_id = 3 [(.google.api.field_behavior) = OPTIONAL];</code>

@return The bytes for backupId.
java-valkey/proto-google-cloud-valkey-v1/src/main/java/com/google/cloud/memorystore/v1/BackupInstanceRequest.java