DeterministicKey: override hasPrivKey and getSecretBytes to reflect the private key derivation strategy used.

core/src/main/java/org/bitcoinj/crypto/DeterministicKey.java

@@ -304,6 +304,18 @@ public class DeterministicKey extends ECKey {
         return super.isPubKeyOnly() && (parent == null || parent.isPubKeyOnly());
     }
 
+    /** {@inheritDoc} */
+    @Override
+    public boolean hasPrivKey() {
+        return findOrDerivePrivateKey() != null;
+    }
+
+    @Nullable
+    @Override
+    public byte[] getSecretBytes() {
+        return priv != null ? getPrivKeyBytes() : null;
+    }
+
     /**
      * A deterministic key is considered to be encrypted if it has access to encrypted private key bytes, OR if its
      * parent does. The reason is because the parent would be encrypted under the same key and this key knows how to

core/src/main/java/org/bitcoinj/wallet/RedeemData.java

@@ -61,18 +61,9 @@ public class RedeemData {
      * Returns the first key that has private bytes
      */
     public ECKey getFullKey() {
-        for (ECKey key : keys) {
+        for (ECKey key : keys)
-            //TODO: don't use exception catching here to test. It's better to use hasPrivKey, but currently it's not working
+            if (key.hasPrivKey())
-            // as expected for DeterministicKeys (it doesn't test if it's possible to derive private key)
+                return key;
-            try {
-                if (key.getPrivKey() != null)
-                    return key;
-            } catch (IllegalStateException e) {
-                // no private bytes. Proceed to the next key
-            } catch (ECKey.MissingPrivateKeyException e) {
-
-            }
-        }
         return null;
     }
 }