No of Image URL Hits ...

Map<String, String> urlmap = new HashMap<>();
Set<String> urlset = new HashSet<>();
for (int i = 0; i < NetworkImageView.imageUrlList.size(); i++) {
    urlset.add(NetworkImageView.imageUrlList.get(i));
    urlmap.put("ImageUrl-" + i, NetworkImageView.imageUrlList.get(i));
}
urlmap.size();
urlset.size();
/*
for (int i = 0; i < urlmap.size(); i++) {
    urlset.add(NetworkImageView.imageUrlList.get(i));
    urlmap.put("ImageUrl-" + i, NetworkImageView.imageUrlList.get(i));
}*/


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Map<String, String> urlmap = new HashMap<>();
Set<String> urlset = new HashSet<>();
for (int i = 0; i < NetworkImageView.imageUrlList.size(); i++) {
    //urlset.add(NetworkImageView.imageUrlList.get(i));
    urlmap.put("ImageUrl-" + i, NetworkImageView.imageUrlList.get(i));
}
//urlmap.size();
//urlset.size();
for (String s : new ConcurrentHashMap<>(urlmap).keySet()) {
    String value = urlmap.get(s);
    for (Map.Entry<String, String> ss : new ConcurrentHashMap<>(urlmap)
            .entrySet()) {
        if (s.equalsIgnoreCase(ss.getKey()) && value.equalsIgnoreCase(ss.getValue())) {
            //urlmap.remove(ss.getKey());
            urlset.add(ss.getKey());
        }
    }
}