Maven, Proguard and JDK8

Question

I'm trying to contribute to the Parceler library but I'm having issues with maven android plugin, obfuscation and jdk8.

It is well known issue and I've tried to fix it by installing latest tool and specifying specific proguard.jar path. But looks like it is still failing. So looking if someone can lead me in the right direction.

Meanwhile I'm digging more.

UPD Here is error that I have:

Caused by: java.io.IOException: Can't process class [com/oracle/net/Sdp$1.class] (Unsupported class version number [52.0] (maximum 51.0, Java 1.7))
[INFO]  at proguard.io.ClassReader.read(ClassReader.java:112)
[INFO]  at proguard.io.FilteredDataEntryReader.read(FilteredDataEntryReader.java:87)
[INFO]  at proguard.io.JarReader.read(JarReader.java:65)
[INFO]  at proguard.io.DirectoryPump.readFiles(DirectoryPump.java:65)
[INFO]  at proguard.io.DirectoryPump.pumpDataEntries(DirectoryPump.java:53)
[INFO]  at proguard.InputReader.readInput(InputReader.java:226)
[INFO]  ... 6 more
[INFO] Caused by: java.lang.UnsupportedOperationException: Unsupported class version number [52.0] (maximum 51.0, Java 1.7)
[INFO]  at proguard.classfile.util.ClassUtil.checkVersionNumbers(ClassUtil.java:140)
[INFO]  at proguard.classfile.io.LibraryClassReader.visitLibraryClass(LibraryClassReader.java:89)
[INFO]  at proguard.classfile.LibraryClass.accept(LibraryClass.java:301)
[INFO]  at proguard.io.ClassReader.read(ClassReader.java:86)
[INFO]  ... 11 more

Answer 1

Update ProGuard to latest version in Android SDK 'tools' folder from link http://proguard.sourceforge.net/downloads.html