firefly-iii/app/models/Category.php

<?php

/**
 * Category
 *
 * @property integer                                                             $id
 * @property \Carbon\Carbon                                                      $created_at
 * @property \Carbon\Carbon                                                      $updated_at
 * @property string                                                              $name
 * @property integer                                                             $user_id
 * @property string                                                              $class
 * @property-read \Illuminate\Database\Eloquent\Collection|\TransactionJournal[] $transactionjournals
 * @property-read \Illuminate\Database\Eloquent\Collection|\Limit[]              $limits
 * @property-read \Illuminate\Database\Eloquent\Collection|\Transaction[]        $transactions
 * @property-read \User                                                          $user
 * @method static \Illuminate\Database\Query\Builder|\Category whereId($value)
 * @method static \Illuminate\Database\Query\Builder|\Category whereCreatedAt($value)
 * @method static \Illuminate\Database\Query\Builder|\Category whereUpdatedAt($value)
 * @method static \Illuminate\Database\Query\Builder|\Category whereName($value)
 * @method static \Illuminate\Database\Query\Builder|\Category whereUserId($value)
 * @method static \Illuminate\Database\Query\Builder|\Category whereClass($value)
 */
class Category extends Component
{
    protected $isSubclass = true;

    /**
     * @return \Illuminate\Database\Eloquent\Relations\BelongsToMany
     */
    public function transactionjournals()
    {
        return $this->belongsToMany('TransactionJournal', 'component_transaction_journal', 'component_id');
    }
}