Java Collection How to - Get lower key from NavigableMap

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Question

We would like to know how to get lower key from NavigableMap.

Answer

        /*from w  ww.j  av  a  2  s .c o m*/

import java.util.Calendar;
import java.util.Locale;
import java.util.Map;
import java.util.NavigableMap;
import java.util.TreeMap;

public class NavigableMapSample {
  public static void main(String args[]) {
    Calendar now = Calendar.getInstance();
    Locale locale = Locale.getDefault();

    Map<String, Integer> names = now.getDisplayNames(Calendar.DAY_OF_WEEK, Calendar.LONG, locale);
    NavigableMap<String, Integer> nav = new TreeMap<String, Integer>(names);
    System.out.printf("Whole list:%n%s%n", nav);
    System.out.printf("Key lower before Sunday: %s%n", nav.lowerKey("Sunday"));
  }
}

The code above generates the following result.

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