@java.lang.Override
    public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
      if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(key_)) {
        com.google.protobuf.GeneratedMessageV3.writeString(output, 1, key_);
      }
      if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(value_)) {
        com.google.protobuf.GeneratedMessageV3.writeString(output, 2, value_);
      }
      getUnknownFields().writeTo(output);
    }
<pre>
The value of the label attached to the product. Cannot be empty and
cannot exceed 128 bytes.
</pre>

<code>string value = 2;</code>

@return The bytes for value.
java-vision/proto-google-cloud-vision-v1p3beta1/src/main/java/com/google/cloud/vision/v1p3beta1/Product.java