Get size of TreeMap example

With this example we are going to demonstrate how to get the size of a TreeMap, that is the number of key value pairs that the TreeMap contains. In short, to get the size of a TreeMap you should:

• Create a new TreeMap.
• Populate the map with elements, with put(K key, V value) API method of TreeMap.
• Invoke size() API method of TreeMap. The method returns the number of key value pairs stored in the TreeMap.

Let’s take a look at the code snippet that follows:

package com.javacodegeeks.snippets.core;

import java.util.TreeMap;
 
public class SizeTreeMap {
 
  public static void main(String[] args) {
 
    // Create a TreeMap and populate it with elements
    TreeMap treeMap = new TreeMap();
    treeMap.put("key_1","element_1");
    treeMap.put("key_3","element_3");
    treeMap.put("key_2","element_2");
    treeMap.put("key_4","element_4");
    treeMap.put("key_5","element_5");

    // int size() operation returns the number of key value pairs stored in TreeMap    
    System.out.println("Size of TreeMap : " + treeMap.size());
  }
}

Output:

Size of TreeMap : 5

 
This was an example of how to get the size of a TreeMap in Java.