Main.java revision 5d88337a18dd35554b08813334d255e34f68fdfa 
1import java.nio.charset.Charset;
2import java.util.ArrayList;
3import java.util.Arrays;
4import java.util.Collections;
5import java.util.HashSet;
6import java.util.List;
7import java.util.Map;
8import java.util.SortedMap;
9import java.util.Set;
10
11public class Main {
12    static public void main(String[] args) throws Exception {
13        // These charsets must be provided; anything else is optional.
14        List<String> standardCharsets = Arrays.asList("US-ASCII", "ISO-8859-1",
15                "UTF-8", "UTF-16BE", "UTF-16LE", "UTF-16");
16
17        SortedMap<String, Charset> all = Charset.availableCharsets();
18        Set<String> needed = new HashSet<String>(standardCharsets);
19        for (Map.Entry<String, Charset> e : all.entrySet()) {
20            String canonicalName = e.getKey();
21            needed.remove(canonicalName);
22        }
23        System.out.println("Missing: " + needed);
24    }
25}
26