List various things

Listing.java

import java.lang.reflect.Method;
import java.nio.charset.Charset;
import java.security.Provider;
import java.security.Security;
import java.text.DateFormat;
import java.util.*;


class Listing {
    public static void main(String[] args) throws Exception {
        if (args.length == 0) {
            System.out.print("Usage: java Listing ");
            boolean first = true;
            for (Method m: Listing.class.getDeclaredMethods()) {
                String n = m.getName();
                if (!n.equals("main")) {
                    if (!first) System.out.print("|");
                    System.out.print(n);
                    first = false;
                }
            }
            System.out.println();
            return;
        }
        Listing.class.getMethod(args[0]).invoke(null);
    }

    public static void alg() throws Exception {
        Provider[] providers = Security.getProviders();
        for (int i=0; i<providers.length; i++) {
            Iterator p = providers[i].keySet().iterator();
            while (p.hasNext()) {
                Object o = p.next();
                System.out.println(o + ": " + providers[i].get(o) + " - " + providers[i]);
            }
        }
    }

    public static void prop() {
        for (Object o: System.getProperties().keySet()) {
            System.out.println(o + ": " + System.getProperty((String)o));
        }
    }

    public static void locale() {
        for (Locale loc: Locale.getAvailableLocales()) {
            System.out.println(loc + ": " + loc.getDisplayName());
        }
    }

    public static void charset() {
        for (String c: Charset.availableCharsets().keySet()) {
            System.out.println(c + ": " + Charset.forName(c).displayName());
        }
    }

    public static void env() {
        for (String s: System.getenv().keySet()) {
            System.out.println(s + ": " + System.getenv(s));
        }
    }

    public static void tz() {
        Date now = new Date();
        Map<String,StringBuilder> names =
                new LinkedHashMap<String,StringBuilder>();
        String[] ids = TimeZone.getAvailableIDs();
        Arrays.sort(ids, new Comparator<String>() {
            @Override
            public int compare(String o1, String o2) {
                TimeZone z1 = TimeZone.getTimeZone(o1);
                TimeZone z2 = TimeZone.getTimeZone(o2);
                return z1.getRawOffset() - z2.getRawOffset();
            }
        });
        for (String id: ids) {
            TimeZone z = TimeZone.getTimeZone(id);
            String name = z.getDisplayName();
            DateFormat df = DateFormat.getTimeInstance();
            df.setTimeZone(z);
            long off = z.getRawOffset();
            String sign = name + off + z.useDaylightTime();
            if (!names.containsKey(sign)) {
                StringBuilder sb = new StringBuilder();
                sb.append("GMT");
                sb.append(off>0?'+':'-');
                if (off < 0) off = -off;
                sb.append(String.format("%02d:%02d - ", off/60000/60, off/60000%60));
                sb.append(String.format("%11s %s- %s - ", df.format(now), (z.inDaylightTime(now)?"DST ":"    "), name));
                sb.append(z.getID());
                names.put(sign, sb);
            } else {
                names.get(sign).append(", ").append(z.getID());
            }
        }
        for (String s: names.keySet()) {
            System.out.println(names.get(s));
        }
    }
}