Hash Key

package agency.syzygy.dollop.com.demoexamples;
import android.content.pm.PackageInfo;

import android.content.pm.PackageManager;

import android.content.pm.Signature;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Base64;

import android.util.Log;
import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;
public class MainActivity extends AppCompatActivity {

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);   

     generateHashkey();    }
    public void generateHashkey() {
        try {
            PackageInfo info = getPackageManager().getPackageInfo(
                    "agency.syzygy.dollop.com.demoexamples",
                    PackageManager.GET_SIGNATURES);
            for (Signature signature : info.signatures) {
                MessageDigest md = MessageDigest.getInstance("SHA");
                md.update(signature.toByteArray());


                Log.e("Hash key", "" + Base64.encodeToString(md.digest(),
                        Base64.NO_WRAP));
            }
        } catch (PackageManager.NameNotFoundException e) {
            Log.d("Name not found", e.getMessage(), e);

        } catch (NoSuchAlgorithmException e) {
            Log.d("Error", e.getMessage(), e);
        }
    }
}

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