[1.7.10] Confusion with leaves

[TheLynx]

I'm new to the whole modding thing, so this should be a simple fix.  As we know leaves are divided into two different blocks.  Blocks.leaves and Blocks.leaves 2.  I need to know how to specifically check for one type of leaves, not just the entire group.  Here's an example:

if (event.block == /*oakLeaves*/)
{
//CODE
}

 

I know that oak leaves are 18:0, but I don't understand how to check the datavalue of the block.

[TheLynx]

Hm.  That's helpful but I'm not sure how to implement this.

[TheLynx]

"World#getBlockMetadata"

 

That.  I can't find any examples of how this is to be used to get what I want.  I'm not very familiar with the API, so an example would be helpful.