HierarchyNodeInheritanceValueMap

Let us understand this with below example, 

Given: /content/parent/page/jcr:content/footer/image/@width, the HierarchyNodeInheritanceValueMap will search for a footer/image/@width property in:

• /content/parent/page/jcr:content/footer/image/@width
• /content/parent/jcr:content/footer/image/@width
• /content/jcr:content/footer/image/@width

Having not found it in any of those locations, it will then return null. 

Note that HierarchyNodeInheritanceValueMap searches only the page hierarchy. It will not (for instance), look in:

• /content/parent/page/jcr:content/footer/@width

Refer:

https://dev.day.com/docs/en/cq/current/javadoc/com/day/cq/commons/inherit/HierarchyNodeInheritanceValueMap.html