Laravel 5.3 Does protected variables in a Model act as constructor

I'm new to Laravel and I noticed some are similar to Java, some aren't. I guess it's because it uses OOP style.

I'm following a video tutorial for beginners and came across the protected modifier (if I'm correct).

I originally learned programming in Java. Below are three php file definitions.

Does the protected $fillable in the Product class act like a constructor in Java which requires you to supply values before you can create an instance of the class? (in this case, Product Class)

ProductTableSeeder.php

<?php

use Illuminate\Database\Seeder;

class ProductTableSeeder extends Seeder
{
    /**
     * Run the database seeds.
     *
     * @return void
     */
    public function run()
    {

        $product = new \App\Product([
            'imagePath' => 'someImagePathURL',
            'title' => 'Harry Potter',
            'description' => 'Super cool - at least as a child.',
            'price' => 10
        ]);
        $product->save();
    }
}

Product.php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Product extends Model
{
    protected $fillable = ['imagePath','title','description','price'];
}

create_products_table.php

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateProductsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('products', function (Blueprint $table) {
            $table->increments('id');
            $table->timestamps();
            $table->string('imagePath');
            $table->string('title');
            $table->text('description');
            $table->integer('price');
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('products');
    }
}

The line $product = new \App\Product I understand to be the instantiation part.

I'd appreciate any useful explanation to this.

Thank you.

via Chebli Mohamed