import java.io.*; import java.util.*; class Comp implements Comparator <String> { public int compare (String k1, String k2) { return -k1.compareTo(k2); } } public class Test { public static void main(String args[]) throws IOException { TreeMap <String, Integer> a = new TreeMap <String, Integer> (); a.put("abc", new Integer(10)); a.put("xyz", new Integer(20)); a.put("kkk", new Integer(30)); System.out.println(a.containsKey("abc")); System.out.println(a.containsValue(10)); System.out.println(a.get("abc")); Map.Entry x = a.lastEntry(); System.out.println(x.getKey() + " " + x.getValue()); // コンパレータを使用する場合(降順) Comparator<String> cp = new Comp(); TreeMap <String, Integer> b = new TreeMap <String, Integer> (cp); b.put("abc", new Integer(10)); b.put("xyz", new Integer(20)); b.put("kkk", new Integer(30)); System.out.println(b.lastKey()); } }
true true 10 xyz 20 abc