Provides an API and implementations of metadata crosswalks, which are directional mappings from one schema to another, performed in the context of Item ingestion or dissemination. Most crosswalks are driven by a mapping in a file, which reside in `config/crosswalks`.

## Crosswalk Interfaces

The principle interfaces are for ingest and dissemination contexts, i.e. the IngestionCrosswalk interface consists of the methods:

`public void ingest(Context context, DSpaceObject dso, List metadata)`
`public void ingest(Context context, DSpaceObject dso, Element root)`

The DisseminationCrosswalk interface has methods:

`public Namespace[] getNamespaces()`
`public String getSchemaLocation()`
`public boolean canDisseminate(DSpaceObject dso)`
`public List disseminateList(DSpaceObject dso)`
`public Element disseminateElement(DSpaceObject dso)`

## Crosswalk Implementations

Crosswalks exist for many formats, includings DC, QDC, METs, MODs, Premis, and a general implementation employing an XSLT stylesheet.