diff --git a/pgpainless-core/src/main/java/org/pgpainless/key/collection/PGPKeyRingCollection.java b/pgpainless-core/src/main/java/org/pgpainless/key/collection/PGPKeyRingCollection.java
index e7e772bd..760977a3 100644
--- a/pgpainless-core/src/main/java/org/pgpainless/key/collection/PGPKeyRingCollection.java
+++ b/pgpainless-core/src/main/java/org/pgpainless/key/collection/PGPKeyRingCollection.java
@@ -1,13 +1,36 @@
+/*
+ * Copyright 2021 Flowcrypt a.s. Copyright 2021 Paul Schaub
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 package org.pgpainless.key.collection;
 
-import org.bouncycastle.openpgp.*;
+import org.bouncycastle.openpgp.PGPException;
+import org.bouncycastle.openpgp.PGPKeyRing;
+import org.bouncycastle.openpgp.PGPObjectFactory;
+import org.bouncycastle.openpgp.PGPPublicKeyRing;
+import org.bouncycastle.openpgp.PGPPublicKeyRingCollection;
+import org.bouncycastle.openpgp.PGPSecretKeyRing;
+import org.bouncycastle.openpgp.PGPSecretKeyRingCollection;
 import org.bouncycastle.openpgp.operator.KeyFingerPrintCalculator;
 
 import javax.annotation.Nonnull;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
 
 /**
  * This class describes a logic of handling a collection of different {@link PGPKeyRing}. The logic was inspired by
diff --git a/pgpainless-core/src/test/java/org/pgpainless/key/parsing/KeyRingReaderTest.java b/pgpainless-core/src/test/java/org/pgpainless/key/parsing/KeyRingReaderTest.java
index 3eeec7c1..02b1cea2 100644
--- a/pgpainless-core/src/test/java/org/pgpainless/key/parsing/KeyRingReaderTest.java
+++ b/pgpainless-core/src/test/java/org/pgpainless/key/parsing/KeyRingReaderTest.java
@@ -17,7 +17,12 @@ package org.pgpainless.key.parsing;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
-import java.io.*;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
 import java.net.URISyntaxException;
 import java.net.URL;
 import java.nio.charset.StandardCharsets;
@@ -27,7 +32,12 @@ import java.security.NoSuchAlgorithmException;
 import java.util.ArrayList;
 import java.util.Collection;
 
-import org.bouncycastle.openpgp.*;
+import org.bouncycastle.openpgp.PGPException;
+import org.bouncycastle.openpgp.PGPPublicKeyRing;
+import org.bouncycastle.openpgp.PGPPublicKeyRingCollection;
+import org.bouncycastle.openpgp.PGPSecretKeyRing;
+import org.bouncycastle.openpgp.PGPSecretKeyRingCollection;
+import org.bouncycastle.openpgp.PGPUtil;
 import org.junit.jupiter.api.Test;
 import org.pgpainless.PGPainless;
 import org.pgpainless.implementation.ImplementationFactory;