Home » Core Java » util » TreeMap » Remove mapping from TreeMap example

About Byron Kiourtzoglou

Byron is a master software engineer working in the IT and Telecom domains. He is an applications developer in a wide variety of applications/services. He is currently acting as the team leader and technical architect for a proprietary service creation and integration platform for both the IT and Telecom industries in addition to a in-house big data real-time analytics solution. He is always fascinated by SOA, middleware services and mobile development. Byron is co-founder and Executive Editor at Java Code Geeks.

Remove mapping from TreeMap example

This is an example of how to remove mapping from a TreeMap, that is removing a key value pair from a TreeMap. Removing mapping from a TreeMap implies that you should:

  • Create a new TreeMap.
  • Populate the map with elements, with put(K key, V value) API method of TreeMap.
  • Invoke remove(Object o) API method of TreeMap with a key as parameter. It removes the key value pair from the map. It returns either the value mapped with the key previously or null if no value was mapped.

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

package com.javacodegeeks.snippets.core;

import java.util.TreeMap;
 
public class RemoveMappingTreeMap {
 
  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_2","element_2");
    treeMap.put("key_3","element_3");
 
    System.out.println("TreeMap contains : " + treeMap);

    /*

Object remove(Object key) operantion removes a key value pair from TreeMap. 

It returns either the value mapped with the key previously or null if no value was mapped.     
    */
    Object value = treeMap.remove("key_2");

    System.out.println("After removing value : " + value + " TreeMap contains : " + treeMap);
 
  }
}

Output:

TreeMap contains : {key_1=element_1, key_2=element_2, key_3=element_3}
After removing value : element_2 TreeMap contains : {key_1=element_1, key_3=element_3}

 
This was an example of how to remove mapping from a TreeMap in Java.

Do you want to know how to develop your skillset to become a Java Rockstar?

Subscribe to our newsletter to start Rocking right now!

To get you started we give you our best selling eBooks for FREE!

 

1. JPA Mini Book

2. JVM Troubleshooting Guide

3. JUnit Tutorial for Unit Testing

4. Java Annotations Tutorial

5. Java Interview Questions

6. Spring Interview Questions

7. Android UI Design

 

and many more ....

 

Receive Java & Developer job alerts in your Area

 

Subscribe
Notify of
guest

This site uses Akismet to reduce spam. Learn how your comment data is processed.

0 Comments
Inline Feedbacks
View all comments