Android: Key Hash 얻기 (kotlin)

import android.os.Build
import android.content.pm.PackageManager
import android.util.Base64
import androidx.annotation.RequiresApi
import java.security.MessageDigest
import android.util.Log


class MainActivity : AppCompatActivity() {

   @RequiresApi(Build.VERSION_CODES.P)
   override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      setContentView(R.layout.activity_main)
        
      try {
         val packageInfo = packageManager.getPackageInfo(
             packageName, PackageManager.GET_SIGNING_CERTIFICATES
         )      
         val signingInfo = packageInfo.signingInfo.apkContentsSigners
   
         for (signature in signingInfo) {
            val messageDigest = MessageDigest.getInstance("SHA")
            messageDigest.update(signature.toByteArray())
            val keyHash = String(Base64.encode(messageDigest.digest(), 0))
            Log.d("KeyHash", keyHash)
         }
         
      } catch (e: Exception) {
         Log.e("Exception", e.toString())
      }
   }
}