TreeMap ceilingKey() method in java
example of TreeMap ceilingKey(K key) method when it returns null
import java.util.NavigableMap;
import java.util.TreeMap;
public class TreeMapCeilingkeyDemo
{
public static void main(String[] args)
{
NavigableMap<Integer, String> nm = new TreeMap<Integer, String>();
nm.put(10, "apple");
nm.put(20, "banana");
nm.put(30, "cherry");
nm.put(40, "fig");
nm.put(60, "grape");
nm.put(70, "kiwifruit");
// 200 is not present in map
// or any key greater than 200
// hence returns null
System.out.println("Ceiling key for 200: " + nm.ceilingKey(200));
}
}
import java.util.NavigableMap;
import java.util.TreeMap;
public class TreeMapCeilingkeyDemo
{
public static void main(String[] args)
{
NavigableMap<Integer, String> nm = new TreeMap<Integer, String>();
nm.put(10, "apple");
nm.put(20, "banana");
nm.put(30, "cherry");
nm.put(40, "fig");
nm.put(60, "grape");
nm.put(70, "kiwifruit");
// 60 is least value > 50
// it is returned as key.
System.out.println("Ceiling key for 50: " + nm.ceilingKey(50));
}
}
example on TreeMap ceilingKey(K key) method when it returns ClassCastException
import java.util.NavigableMap;
import java.util.TreeMap;
public class TreeMapCeilingkeyDemo
{
public static void main(String[] args)
{
NavigableMap<Object, String> tm = new TreeMap<Object, String>();
tm.put(10, "apple");
tm.put(20, "banana");
tm.put(30, "cherry");
tm.put(40, "fig");
tm.put(60, "grape");
tm.put(70, "kiwifruit");
try
{
// returns ClassCastException
// we cannot compare String object with an Integer object
System.out.println("Ceiling key entry for \"asd\": " + tm.ceilingKey(new String("mango")));
}
catch(Exception ex)
{
System.out.println("Exception: " + ex);
}
}
}