illegal.argument exception

[Andrew Striletskyi]

I have a part of script . On Jira 7 this script succesfully working , but in jira 6.4 I see an error illegalArgument exception (in line with "def PriorityQueue") . Code: 
How to fix it?

class Agent {

 ApplicationUser user;

 int issueCount;

 long lastAssignedTime;

}



def groups = ComponentAccessor.getGroupManager() as GroupManager

def agents = groups.getUsersInGroup("jira-software-users")







def userManager = ComponentAccessor.getUserManager() as UserManager

def user = ComponentAccessor.jiraAuthenticationContext.loggedInUser

def jqlQueryParser = ComponentAccessor.getComponent(JqlQueryParser.class)

def searchProvider = ComponentAccessor.getComponent(SearchProvider.class)









def PriorityQueue<Agent> agentPQ = new PriorityQueue<>(agents.size(), new Comparator<Agent>() {

 @Override

 int compare(Agent o1, Agent o2) {

 if(o1.issueCount == o2.issueCount){

 if(o2.lastAssignedTime == o1.lastAssignedTime){

 return o1.user.name.compareTo(o2.user.name)

 }else{

 return o1.lastAssignedTime.compareTo(o2.lastAssignedTime)

 }

 }else{

 return o1.issueCount - o2.issueCount

 }

 }

})