### Question:
PositionListIndex { @Override public int hashCode() { final int prime = 31; int result = 1; List<LongOpenHashSet> setCluster = convertClustersToSets(clusters); Collections.sort(setCluster, new Comparator<LongSet>() { @Override public int compare(LongSet o1, LongSet o2) { return o1.hashCode() - o2.hashCode(); } }); result = prime * result + (setCluster.hashCode()); return result; } PositionListIndex(List<LongArrayList> clusters);  PositionListIndex(); PositionListIndex intersect(PositionListIndex otherPLI); List<LongArrayList> getClusters(); @Override PositionListIndex clone(); @Override int hashCode(); @Override boolean equals(Object obj); Long2LongOpenHashMap asHashMap(); long size(); boolean isEmpty(); boolean isUnique(); long getRawKeyError();  }### Answer:
@Test public void testHashCode() { PositionListIndex firstPLI = fixture.getFirstPLI(); PositionListIndex permutatedfirstPLI = fixture.getPermutatedFirstPLI(); assertEquals(firstPLI, firstPLI); assertEquals(firstPLI.hashCode(), firstPLI.hashCode()); assertEquals(firstPLI, permutatedfirstPLI); assertEquals(firstPLI.hashCode(), permutatedfirstPLI.hashCode()); }