HierarchyResolver (Apache Jackrabbit 2.23.1-beta API)

All Known Implementing Classes:

CachingMultiIndexReader, JackrabbitIndexReader, SearchIndex.CombinedIndexReader
```
public interface HierarchyResolver
```
HierarchyResolver extends an IndexReader with the ability to resolve a JCR hierarchy.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`int[]`	`getParents(int n, int[] docNumbers)`	Returns the document number of the parent of `n` or an empty array if `n` does not have a parent (`n` is the root node).

- Method Detail
  - getParents
```
int[] getParents(int n,
                 int[] docNumbers)
          throws IOException
```
    Returns the document number of the parent of n or an empty array if n does not have a parent (n is the root node).
    
    Parameters:
    
    n - the document number.
    
    docNumbers - an array for reuse. An implementation should use the passed array as a container for the return value, unless the length of the returned array is different from docNumbers. In which case an implementation will create a new array with an appropriate size.
    
    Returns:
    
    the document number of n's parent.
    
    Throws:
    
    IOException - if an error occurs while reading from the index.