public Builder clearCollection() {
      bitField0_ = (bitField0_ & ~0x00000002);
      collection_ = null;
      if (collectionBuilder_ != null) {
        collectionBuilder_.dispose();
        collectionBuilder_ = null;
      }
      onChanged();
      return this;
    }
<pre>
Required. The collection resource to be created.
</pre>

<code>
.google.cloud.visionai.v1.Collection collection = 2 [(.google.api.field_behavior) = REQUIRED];
</code>
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/CreateCollectionRequest.java