licenser - adds copyright notice to all your source files

go get github.com/emicklei/licenser

Help

Usage: licenser [flags] [path...]

-d	dry run, see which files would change
-e string
        file extension for which the copyright notice must be added (default ".go")
-f string
        filename that contains the copyright notice
-r	recursively search for files
-s	if true then use the /* ... */ method for writing the notice else use //

Example

licenser -d -r -s -e ".java" -f LICENSE .

Example Apache v2

Copyright 2017 Me, myself and I

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.