Latest version of com.google.protobuf:protobuf-java
https://javadoc.io/doc/com.google.protobuf/protobuf-java
Current version 3.0.0-alpha-3
https://javadoc.io/doc/com.google.protobuf/protobuf-java/3.0.0-alpha-3
package-list path (used for javadoc generation -link option)
https://javadoc.io/doc/com.google.protobuf/protobuf-java/3.0.0-alpha-3/package-list