The higherEntry() method of java.util.TreeMap class is used to return a key-value mapping associated with the least key strictly greater than the given key, or null if there is no such key.
Syntax:
public Map.Entry higherEntry(K key)
Parameters: This method takes the key as a parameter.
Return Value: This method returns an entry with the least key greater than key, or null if there is no such key.
Exception: This method throws the NullPointerException if the specified key is null and this map uses natural ordering, or its comparator does not permit null keys.
Below are the examples to illustrate the higherEntry() method
Example 1:
Java
// Java program to demonstrate// higherEntry() method// for <Integer, String> valueimport java.util.*;public class GFG1 { public static void main(String[] argv) throws Exception { try { // creating object of TreeMap<Integer, String> TreeMap<Integer, String> treemap = new TreeMap<Integer, String>(); // populating tree map treemap.put(1, "One"); treemap.put(2, "Two"); treemap.put(3, "Three"); treemap.put(4, "Four"); treemap.put(5, "Five"); // printing the TreeMap System.out.println("TreeMap: " + treemap); // getting higher entry value for 3 Map.Entry<Integer, String> value = treemap.higherEntry(3); // printing the value System.out.println("The higherEntry value " + " for 3: " + value); } catch (NullPointerException e) { System.out.println("Exception thrown : " + e); } }} |
Output:
TreeMap: {1=One, 2=Two, 3=Three, 4=Four, 5=Five}
The higherEntry value for 3: 4=Four
Example 2: For NullPointerException
Java
// Java program to demonstrate// higherEntry() method// for NullPointerExceptionimport java.util.*;public class GFG1 { public static void main(String[] argv) throws Exception { try { // creating object of TreeMap<Integer, String> TreeMap<Integer, String> treemap = new TreeMap<Integer, String>(); // populating tree map treemap.put(1, "One"); treemap.put(2, "Two"); treemap.put(3, "Three"); treemap.put(4, "Four"); treemap.put(5, "Five"); // printing the TreeMap System.out.println("TreeMap: " + treemap); // getting higher entry value for null System.out.println("Trying to get " + "the higher entry value" + " for null"); Map.Entry<Integer, String> value = treemap.higherEntry(null); // printing the value System.out.println("Value is: " + value); } catch (NullPointerException e) { System.out.println("Exception thrown : " + e); } }} |
Output:
TreeMap: {1=One, 2=Two, 3=Three, 4=Four, 5=Five}
Trying to get the higher entry value for null
Exception thrown : java.lang.NullPointerException
