PGPKeyRing: Add getKeyIdentifier()

Author: vanitasvitae

pg/src/main/java/org/bouncycastle/openpgp/PGPKeyRing.java

@@ -93,6 +93,16 @@ static void readUserIDs(
         }
     }
 
+    /**
+     * Return the {@link KeyIdentifier} of this key rings primary key.
+     *
+     * @return primary key identifier
+     */
+    public KeyIdentifier getKeyIdentifier()
+    {
+        return getPublicKey().getKeyIdentifier();
+    }
+
     /**
      * Return the first public key in the ring.  In the case of a {@link PGPSecretKeyRing}
      * this is also the public key of the master key pair.