align shared files copyright/comments to bitcoinj's

src/java/org/bitcoin/NativeSecp256k1.java

@@ -1,3 +1,20 @@
+/*
+ * Copyright 2013 Google Inc.
+ * Copyright 2014-2016 the libsecp256k1 contributors
+ *
+ * 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.bitcoin;
 
 import java.nio.ByteBuffer;
@@ -10,9 +27,15 @@ import java.util.concurrent.locks.ReentrantReadWriteLock;
 import static org.bitcoin.NativeSecp256k1Util.*;
 
 /**
- * This class holds native methods to handle ECDSA verification.
+ * <p>This class holds native methods to handle ECDSA verification.</p>
- * You can find an example library that can be used for this at
+ *
- * https://github.com/sipa/secp256k1
+ * <p>You can find an example library that can be used for this at https://github.com/bitcoin/secp256k1</p>
+ *
+ * <p>To build secp256k1 for use with bitcoinj, run
+ * `./configure --enable-jni --enable-experimental --enable-module-schnorr --enable-module-ecdh`
+ * and `make` then copy `.libs/libsecp256k1.so` to your system library path
+ * or point the JVM to the folder containing it with -Djava.library.path
+ * </p>
  */
 public class NativeSecp256k1 {
 

src/java/org/bitcoin/NativeSecp256k1Util.java

@@ -1,3 +1,19 @@
+/*
+ * Copyright 2014-2016 the libsecp256k1 contributors
+ *
+ * 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.bitcoin;
 
 public class NativeSecp256k1Util{

src/java/org/bitcoin/Secp256k1Context.java

@@ -1,8 +1,24 @@
+/*
+ * Copyright 2014-2016 the libsecp256k1 contributors
+ *
+ * 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.bitcoin;
 
 /**
  * This class holds the context reference used in native methods 
-   to handle ECDSA operations.
+ * to handle ECDSA operations.
  */
 public class Secp256k1Context {
   private static final boolean enabled; //true if the library is loaded