How to user compose to update library in PHP

1.step up composer
2.Link to php.exe
3.In project open file composer.json

{
    "name": "zendframework/skeleton-application",
    "description": "Skeleton Application for ZF2",
    "license": "BSD-3-Clause",
    "keywords": [
        "framework",
        "zf2"
    ],
    "homepage": "http://framework.zend.com/",
    "minimum-stability": "dev",
    "require": {
        "php": ">=5.3.3",
        "zendframework/zendframework": "2.0.2",
 "doctrine/doctrine-mongo-odm-module": "dev-master"
    }
}

4. Run php composer.phar install