Java ConcurrentHashMap put() Method

The put() method of ConcurrentHashMap class maps the specified key to the specified value in this table.

Syntax

Parameter

key - key with which the specified value is to be associated

value - value to be associated with the specified key

Returns

The previous value associated with key, or null if there was no mapping for key

Throws

NullPointerException.

Example 1

import java.util.*; 
import java.util.concurrent.*; 
  
public class ConcurrentHashMapputExample1   { 
    public static void main(String[] args) 
    { 
        ConcurrentHashMap<String, Integer>  mymap = new ConcurrentHashMap<String,  Integer>(); 
        mymap.put("AAA", 10); 
        mymap.put("BBB", 15); 
        mymap.put("CCC", 25); 
        mymap.put("DDD", 255); 
        mymap.put("EEE",30); 
        System.out.println(" Mappings are: " +mymap); 
        //  print statement
        System.out.println("is 255  present? ::  "+ mymap.containsValue(255));  //checks if 255 is in the concurrentHashmap 
    } 
}

Test it Now

Output:

Mappings are: {AAA=10, CCC=25, BBB=15, EEE=30, DDD=255}
is 255  present? ::  true

Example 2

import java.util.*; 
import java.util.concurrent.*; 
  
public class ConcurrentHashMapputExample2  { 
    public static void main(String[] args) 
    { 
        ConcurrentHashMap<String, Integer>  map = new ConcurrentHashMap<String,  Integer>(); 
        // put values in  ConcurrentHashMap
        map.put("java", 10); 
        map.put(".net", 15); 
        map.put("python", 20); 
        map.put("c", 25); 
        map.put("c++", 30);  
        // print statement
        System.out.println(" Mappings are: " +map); 
        System.out.println("is java  present? ::  " + map.containsKey("java"));  //print statement
    } 
}

Test it Now

Output:

Mappings are: {python=20, c++=30, java=10, c=25, .net=15}
is java  present? ::  true

Next TopicJava ConcurrentHashMap

← prev next →

For Videos Join Our Youtube Channel: Join Now

Feedback

Send your Feedback to [email protected]

Help Others, Please Share

Learn Latest Tutorials

Splunk

SPSS

Swagger

Transact-SQL

Tumblr

ReactJS

Regex

Reinforcement Learning

R Programming

RxJS

React Native

Python Design Patterns

Python Pillow

Python Turtle

Keras

Preparation

Aptitude

Reasoning

Verbal Ability

Interview Questions

Company Questions

Trending Technologies

Artificial Intelligence

AWS

Selenium

Cloud Computing

Hadoop

ReactJS

Data Science

Angular 7

Blockchain

Git

Machine Learning

DevOps

B.Tech / MCA

DBMS

Data Structures

DAA

Operating System

Computer Network

Compiler Design

Computer Organization

Discrete Mathematics

Ethical Hacking

Computer Graphics

Software Engineering

Web Technology

Cyber Security

Automata

C Programming

C++

Java

.Net

Python

Programs

Control System

Data Mining

Data Warehouse

^{Like/Subscribe us for latest updates or newsletter}