Working with End Points : TreeMap « Collections « Java Tutorial

The firstKey() and lastKey() methods of TreeMap let you quickly access the keys at the end of the map.

If you need to traverse a map backwards(keep getting the last key and the head map before it):

import java.util.TreeMap;

public class MainClass {
  public static void main(String[] a) {

    TreeMap map = new TreeMap();
    map.put("key1", "value1");
    map.put("key2", "value2");
    map.put("key3", "value3");

    if (!map.isEmpty()) {
      Object last = map.lastKey();
      boolean first = true;
      do {
        if (!first) {
          System.out.print(", ");
        last = map.headMap(last).lastKey();
        first = false;
      } while (last != map.firstKey());
key3, key2

9.29.1.TreeMap Class
9.29.2.Viewing Sub Maps
9.29.3.Working with End Points
9.29.4.Get Synchronized Map from TreeMap
9.29.5.Check if a particular key exists in TreeMap
9.29.6.Check if a particular value exists in TreeMap
9.29.7.Get Head Map from TreeMap
9.29.8.Get lowest and highest key stored in TreeMap
9.29.9.Get Set view of Keys from TreeMap
9.29.10.Get TreeMap Size
9.29.11.Get Sub Map from TreeMap
9.29.12.Get Tail Map from TreeMap
9.29.13.Iterate through the values of TreeMap
9.29.14.Remove all values from TreeMap
9.29.15.Remove value from TreeMap
9.29.17.Cache Map