如何检查用户是否接受了读/写联系人的权限？

if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_CONTACTS) == PackageManager.PERMISSION_GRANTED
        && ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_CONTACTS) == PackageManager.PERMISSION_GRANTED) {
    // 已获取读/写联系人权限
} else {
    // 未获取读/写联系人权限
}

private static final int REQUEST_CONTACTS_PERMISSIONS = 1;

private void requestContactsPermissions() {
    ActivityCompat.requestPermissions(this,
            new String[]{Manifest.permission.READ_CONTACTS, Manifest.permission.WRITE_CONTACTS},
            REQUEST_CONTACTS_PERMISSIONS);
}

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    if (requestCode == REQUEST_CONTACTS_PERMISSIONS) {
        if (grantResults.length == 2 &&
                grantResults[0] == PackageManager.PERMISSION_GRANTED &&
                grantResults[1] == PackageManager.PERMISSION_GRANTED) {
            // 用户已授予读/写联系人权限
        } else {
            // 用户未授予读/写联系人权限
        }
    }
}