@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(collection_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 1, collection_);
    }
    if (type_ != com.google.cloud.visionai.v1.CollectionItem.Type.TYPE_UNSPECIFIED.getNumber()) {
      output.writeEnum(2, type_);
    }
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(itemResource_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 3, itemResource_);
    }
    getUnknownFields().writeTo(output);
  }
<pre>
Required. The name of the CollectionItem. Its format depends on the `type`
above. For ASSET:
`projects/{project_number}/locations/{location}/corpora/{corpus}/assets/{asset}`
</pre>

<code>string item_resource = 3 [(.google.api.field_behavior) = REQUIRED];</code>

@return The bytes for itemResource.
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/CollectionItem.java