How to get Current Admin User roles name and email id in Magento 2?

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You can get a first name, last name, and email of current admin user roles by calling User module’s Collection class.

You can fetch current user data by below code snippet,

<?php

namespace Path\To\Block;

use Magento\Backend\Block\Template\Context;
use Magento\Authorization\Model\UserContextInterface;
use Magento\User\Model\ResourceModel\User\CollectionFactory as UserCollectionFactory;

/**
 * CurrentAdminUser block
 */
class CurrentAdminUser extends \Magento\Backend\Block\Template
{
    /**
     * @var UserContextInterface
     */
    protected $userContext;

    /**
     * @var UserCollectionFactory
     */
    private $userCollectionFactory;

    public function __construct(
        Context $context,
        UserContextInterface $userContext,
        UserCollectionFactory $userCollectionFactory,
        array $data = []
    ) {
        $this->userContext = $userContext;
        $this->userCollectionFactory = $userCollectionFactory;
        parent::__construct($context, $data);
    }

    /* Admin User info */
    public function getUserData()
    {
        $collection = $this->userCollectionFactory->create();
        $userId = $this->userContext->getUserId();
        $collection->addFieldToFilter('main_table.user_id', $userId);
        $userData = $collection->getFirstItem();
        return $userData->getData();
    }

Call function, $this->getUserData() to get Output and based on your requirement you can fetch required data.

Result:

Array
(
    [user_id] => 7
    [firstname] => Rakesh
    [lastname] => Jesadiya
    [email] => admin@admintest.com
    [username] => admin
    [password] => 4163549099b7476254e4d4cffba9bb40aa7b92c80906838b630452c7e79e7f7
    [created] => 2019-07-10 11:50:21
    [modified] => 2019-07-18 11:19:06
    [logdate] => 2019-07-18 11:19:06
    [lognum] => 1
    [reload_acl_flag] => 0
    [is_active] => 1
    [extra] => 
    [rp_token] => 
    [rp_token_created_at] => 
    [interface_locale] => en_US
    [failures_num] => 0
    [first_failure] => 
    [lock_expires] => 
    [refresh_token] => 
    [role_name] => Administrators
)