HeadContributable (Hippo Site Toolkit API 15.4.0 API)

```
public interface HeadContributable
```
Interface for abstraction that allows to contribute head elements to the page.
As one of typical use cases, a custom valve placed before AggregationValve may set an instance of this to HstRequestContext and so the AggregationValve will be able to gather all the head elements to contribute to the page.

- Method Summary
  
  All Methods Instance Methods Abstract Methods
  Modifier and Type Method Description
  
  void contributeHeadElements(HstResponse rootResponse)
  Contribute head elements to the given response.

- Method Detail
  - contributeHeadElements
```
void contributeHeadElements(HstResponse rootResponse)
```
    Contribute head elements to the given response.
    
    Parameters:
    
    rootResponse - the root HstResponse through which this can contribute head elements to the page.