List of tags for a specific query - (dotCMS)

##This macro will loop through all the contentlets in a query,
##and create a list of all of tags and how many times they occur
##ie. [{title=shoes, count=4}, {title=achilles, count=1}, {title=cara, count=6}]
##
## This list can then be sorted and thrown back into the page


#### MACRO CODE

#macro (tagListByQuery $query $fieldname)
    #set($tagMap = $contents.getEmptyMap())
    #foreach($content in $dotcontent.pull($query,0,"modDate desc"))
        #foreach($tag in $content.get($fieldname))
            #if(!$tagMap.containsKey($tag))  ## If the list doesn't have my tag already, add it
                #set($dummy = $tagMap.put($tag, 1))
            #else ## If the list has my tag, increment the count value
                #set($currentCount = $tagMap.get($tag))
                #set($newCount = $math.add($currentCount, 1))
                #set($dummy = $tagMap.put($tag, $newCount))
            #end
        #end
    #end

    ## Shuffle everything across into a list where it can be sorted
    #set($tagList = $contents.getEmptyList())
    #foreach($tag in $tagMap.keySet())
        #set($item = $contents.getEmptyMap())
        #set($item = $contents.getEmptyMap())
        #set($dummy = $item.put("title",$tag))
        #set($dummy = $item.put("count",$tagMap.get($tag)))
        #set($dummy = $tagList.add($item))
    #end
#end


#### USAGE EXAMPLE

#tagListByQuery ("+structureName:BlogEntry +live:true" "tag")

<ul>
#foreach ($tag in $sorter.sort($tagList,["count:desc", "title:asc"]))
    <li><strong>$tag.title</strong> - $tag.count</li>
#end
</ul>