Added copyright info

src/main/javassist/tools/Callback.java

@@ -1,3 +1,19 @@
+/*
+ * Javassist, a Java-bytecode translator toolkit.
+ * Copyright (C) 1999- Shigeru Chiba. All Rights Reserved.
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License.  Alternatively, the contents of this file may be used under
+ * the terms of the GNU Lesser General Public License Version 2.1 or later,
+ * or the Apache License Version 2.0.
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ */
+
 package javassist.tools;
 
 import javassist.CannotCompileException;
@@ -29,6 +45,8 @@ import java.util.UUID;
  *     }
  * });
  * }</pre>
+ *
+ * @author Marten Hedborg
  */
 public abstract class Callback {
 

src/test/javassist/tools/CallbackTest.java

@@ -33,7 +33,7 @@ public class CallbackTest extends TestCase {
             }
         });
 
-        // Change class and invoke method();
+        // Change class and invoke method;
         classToChange.toClass();
         new DummyClass().dummyMethod();
     }