public Builder setRegionBytes(com.google.protobuf.ByteString value) {
        if (value == null) {
          throw new NullPointerException();
        }
        checkByteStringIsUtf8(value);
        region_ = value;
        bitField0_ |= 0x00000008;
        onChanged();
        return this;
      }
<pre>
Specifies the region to sign requests with. This can be left blank if
requests should be signed with an empty region.
</pre>

<code>string region = 5;</code>

@param value The bytes for region to set.
@return This builder for chaining.
java-storage-transfer/proto-google-cloud-storage-transfer-v1/src/main/java/com/google/storagetransfer/v1/proto/TransferTypes.java