### Question:
PositionListIndex { public PositionListIndex intersect(PositionListIndex otherPLI) { return calculateIntersection(otherPLI); } 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 testIntersect() { PositionListIndex firstPLI = fixture.getFirstPLI(); PositionListIndex secondPLI = fixture.getSecondPLI(); PositionListIndex expectedPLI = fixture.getExpectedIntersectedPLI(); PositionListIndex actualIntersectedPLI = firstPLI.intersect(secondPLI); assertEquals(expectedPLI, actualIntersectedPLI); }