 abstract class <span class="typeNameLabel">Role</span>
extends java.lang.Object
implements java.io.Serializable</pre>
<div class="block">The roles field is used to describe the purpose of each asset. It is recommended to include one for every asset, to give users a sense of why they might want to make use of the asset. There are some emerging standards that enable clients to take particular action when they encounter particular roles, listed below. But implementors are encouraged to come up with their own 