Errors in Ice4j Source: Duplicate Methods

Question

I am trying to export Ice4j to a jar file to use in my project, but there is an error and I don't know how to fix it because I have never seen this before and Google has little information about it. I copied the files straight from the svn with no edits, so I'll post the source below.

Duplicate methods named spliterator with the parameters () and () are inherited from the types Collection<CandidateHarvester> and Iterable<CandidateHarvester>
Duplicate methods named spliterator with the parameters () and () are inherited from the types Set<CandidateHarvester> and Collection<CandidateHarvester>

The bit of code is below:

public class CandidateHarvesterSet
    extends AbstractSet<CandidateHarvester>
{

The full file is here: https://code.google.com/p/ice4j/source/browse/trunk/src/org/ice4j/ice/harvest/CandidateHarvesterSet.java

Answer 1

For some reason, changing the JRE system library from JRE8 to JRE7 works.