[SOLVED] Scala - bad constant pool tag

Scala - bad constant pool tag

I need to use this project https://github.com/dwins/mapnik2geotools . I proceed step by step, but when I enter sbt run I get this error :

C:\Users\Admin\Downloads\mapnik2geotools-master\mapnik2geotools-

master>sbt run
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=256m; support was removed in 8.0
error: error while loading CharSequence, class file 'C:\Program Files\Java\jdk1.8.0_111\jre\lib\rt.jar(java/lang/CharSequence.class)' is broken
(bad constant pool tag 15 at byte 1501)
[error] Type error in expression
Project loading failed: (r)etry, (q)uit, (l)ast, or (i)gnore?

I have installed scala 2.12.1. Any ideas?

Solution

Project is using scala version 2.9.1 (see build.sbt file) that was released long before java 8 came out. You seem to be running java 8. So you need to downgrade java to java 6 or 7.