Check out example codes for "TreeMap K firstKey() method in java". It will help you in understanding the concepts better.

Code Example 1

import java.util.TreeMap;
public class TreeMapFirstKeyMethodExample
   public static void main(String[] args)
      TreeMap<Integer, String> tm = new TreeMap<Integer, String>();
      tm.put(2, "tejas");
      tm.put(1, "om");
      tm.put(3, "tarun");
      tm.put(6, "siddarth");
      tm.put(5, "fanindra");
      System.out.println("first key of TreeMap: ");
      System.out.println("First key is: " + tm.firstKey());

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