How to count number of issue using searchservice

[Aslam]

I am not a programmer but trying to put code in the plugin 

JIRA Misc Custom Fields to find all the issue that matches the custom field .....and return the count so if the value is greater than 1 than it is duplicate...i found the below code but need help get what i want..

import com.atlassian.jira.bc.issue.search.SearchService;
import com.atlassian.jira.bc.project.component.ProjectComponent;
import com.atlassian.jira.component.ComponentAccessor;
import com.atlassian.jira.project.Project;
import com.atlassian.jira.user.ApplicationUser;
import com.atlassian.jira.user.ApplicationUsers;
import com.atlassian.jira.web.bean.PagerFilter;

String iskey = issue.get("customfield_10500");

String jqlSearch = "summary ~ " + iskey;

SearchService searchService = ComponentAccessor.getComponentOfType(SearchService.class);
ParseResult parseResult = searchService.parseQuery(authenticationContext.getLoggedInUser(), jqlSearch);
int totalIssues = 0;
if (parseResult.isValid()) {
try {
SearchResults results = searchService.search(authenticationContext.getLoggedInUser(), parseResult.getQuery(), PagerFilter.getUnlimitedFilter());
final List<Issue> issues = results.getIssues();
totalIssues = issues.size();
return totalIssues;

} catch (SearchException e) {
e.printStackTrace();
}
}