diff --git a/pgpainless-core/src/main/java/org/pgpainless/key/protection/UnprotectedKeysProtector.java b/pgpainless-core/src/main/java/org/pgpainless/key/protection/UnprotectedKeysProtector.java
deleted file mode 100644
index 5d3f3361..00000000
--- a/pgpainless-core/src/main/java/org/pgpainless/key/protection/UnprotectedKeysProtector.java
+++ /dev/null
@@ -1,33 +0,0 @@
-// SPDX-FileCopyrightText: 2018 Paul Schaub <vanitasvitae@fsfe.org>
-//
-// SPDX-License-Identifier: Apache-2.0
-
-package org.pgpainless.key.protection;
-
-import javax.annotation.Nullable;
-
-import org.bouncycastle.openpgp.operator.PBESecretKeyDecryptor;
-import org.bouncycastle.openpgp.operator.PBESecretKeyEncryptor;
-
-/**
- * Implementation of the {@link SecretKeyRingProtector} which assumes that all handled keys are not password protected.
- */
-public class UnprotectedKeysProtector implements SecretKeyRingProtector {
-
-    @Override
-    public boolean hasPassphraseFor(long keyId) {
-        return true;
-    }
-
-    @Override
-    @Nullable
-    public PBESecretKeyDecryptor getDecryptor(long keyId) {
-        return null;
-    }
-
-    @Override
-    @Nullable
-    public PBESecretKeyEncryptor getEncryptor(long keyId) {
-        return null;
-    }
-}
diff --git a/pgpainless-core/src/main/kotlin/org/pgpainless/key/protection/UnprotectedKeysProtector.kt b/pgpainless-core/src/main/kotlin/org/pgpainless/key/protection/UnprotectedKeysProtector.kt
new file mode 100644
index 00000000..f87c6d3d
--- /dev/null
+++ b/pgpainless-core/src/main/kotlin/org/pgpainless/key/protection/UnprotectedKeysProtector.kt
@@ -0,0 +1,15 @@
+// SPDX-FileCopyrightText: 2023 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+package org.pgpainless.key.protection
+
+/**
+ * Implementation of the [SecretKeyRingProtector] which assumes that all handled keys are not password protected.
+ */
+class UnprotectedKeysProtector : SecretKeyRingProtector {
+    override fun hasPassphraseFor(keyId: Long) = true
+
+    override fun getDecryptor(keyId: Long) = null
+
+    override fun getEncryptor(keyId: Long) = null
+}
\ No newline at end of file