Learnt a few things about how to use HashMaps in JSTL.
To access a hashmap with a key in JSTL.
${map.key} or ${map[key]}
If your key is from some other variable or you need to set the key dynamically
//Create a variable call keyName and set the value to something
<c:set var="keyName" value="${someObject.id}"/>
<c:out value="${map[keyName].id}/>
