Getting request class not found error

[arpitx165]

I have tried to include this library using composer but still i am getting class not found error Can any one tell me how can i fix this one

for including library i used :- require_once 'vendor/autoload.php';

[stil]

Paste the output of composer install execution. You're probably getting some errors while installation.

[arpitx165]

@still : this is my composer.json file

{
"require": {
"stil/curl-easy": "*"
}
}

After running this command : php composer.phar install
Output :
Loading composer repositories with package information
Updating dependencies (including require-dev)

• Installing symfony/event-dispatcher (v2.8.7)
  Downloading: 100%
• Installing stil/curl-easy (v1.1.4)
  Downloading: 100%

symfony/event-dispatcher suggests installing symfony/dependency-injection ()
symfony/event-dispatcher suggests installing symfony/http-kernel ()
Writing lock file
Generating autoload files

I am unable to fix symfony/dependency-injection () and symfony/http-kernel ()