"php artisan app:name AppName" problem in Laravel 5.1

I am having a problem generating an application name in my project. When I generated php artisan app:name AppName, I encountered this error:

PHP Fatal error:  Uncaught ReflectionException: Class AppName\Console\Kernel does not exist in /home/user/Desktop/AppName/vendor/laravel/framework/src/Illuminate/Container/Container.php:741
...

This is my composer.json file:

{
    "name": "laravel/laravel",
    "description": "The Laravel Framework.",
    "keywords": ["framework", "laravel"],
    "license": "MIT",
    "type": "project",
    "require": {
        "php": ">=5.5.9",
        "laravel/framework": "5.1.*",
        "barryvdh/laravel-debugbar": "^2.2",
        "parse/php-sdk" : "1.2.*",
        "graham-campbell/parse": "^2.0"
    },
    "require-dev": {
        "fzaninotto/faker": "~1.4",
        "mockery/mockery": "0.9.*",
        "phpunit/phpunit": "~4.0",
        "phpspec/phpspec": "~2.1"
    },
    "autoload": {
        "classmap": [
            "database"
        ],
        "psr-4": {
            "App\\": "app/"
        }
    },
    "autoload-dev": {
        "classmap": [
            "tests/TestCase.php"
        ]
    },
    "scripts": {
        "post-root-package-install": [
            "php -r \"copy('.env.example', '.env');\""
        ],
        "post-create-project-cmd": [
            "php artisan key:generate"
        ],
        "post-install-cmd": [
            "Illuminate\\Foundation\\ComposerScripts::postInstall",
            "php artisan optimize"
        ],
        "post-update-cmd": [
            "Illuminate\\Foundation\\ComposerScripts::postUpdate",
            "php artisan optimize"
        ]
    },
    "config": {
        "preferred-install": "dist"
    }
}

How can I fix this problem? Thanks in advance!