private void ensureBoundingPolysIsMutable() {
      if (!((bitField0_ & 0x00000004) != 0)) {
        boundingPolys_ =
            new java.util.ArrayList<com.google.cloud.vision.v1.BoundingPoly>(boundingPolys_);
        bitField0_ |= 0x00000004;
      }
    }
<pre>
Required. The Google Cloud Storage URI of the reference image.

The URI must start with `gs://`.
</pre>

<code>string uri = 2 [(.google.api.field_behavior) = REQUIRED];</code>

@param value The bytes for uri to set.
@return This builder for chaining.
java-vision/proto-google-cloud-vision-v1/src/main/java/com/google/cloud/vision/v1/ReferenceImage.java