### Question:
UccGraphTraverser extends GraphTraverser { public void init(List<PositionListIndex> basePLIs, UniqueColumnCombinationResultReceiver resultReceiver, String relationName, List<String> columnNames) throws CouldNotReceiveResultException, ColumnNameMismatchException { this.resultReceiver = resultReceiver; this.relationName = relationName; this.columnNames = columnNames; this.filterNonUniqueColumnCombinationBitsets(basePLIs); this.numberOfColumns = this.calculatedPlis.size(); this.negativeGraph = new PruningGraph(this.numberOfColumns, this.OVERFLOW_THRESHOLD, false); this.positiveGraph = new PruningGraph(this.numberOfColumns, this.OVERFLOW_THRESHOLD, true); this.randomWalkTrace = new LinkedList<>(); this.seedCandidates = this.buildInitialSeeds(); this.holeFinder = new HoleFinder(this.numberOfColumns); } UccGraphTraverser();  UccGraphTraverser(Random random); void setDesiredKeyError(long desiredKeyError); void init(List<PositionListIndex> basePLIs,
                   UniqueColumnCombinationResultReceiver resultReceiver, String relationName,
                   List<String> columnNames);  }### Answer:
@Test public void testTraverseGraph() throws CouldNotReceiveResultException, ColumnNameMismatchException { List<PositionListIndex> pliList = fixture.getPLIList(); LinkedList<String> columnNames = new LinkedList<>(); Integer i; for (i = 0; i < pliList.size(); i++) { columnNames.add(i.toString()); } ImmutableList<String> immutableColumnNames = ImmutableList.copyOf(columnNames); UccGraphTraverser graph = new UccGraphTraverser(); graph.init(fixture.getPLIList(), mock(UniqueColumnCombinationResultReceiver.class), "relation", immutableColumnNames); Collection<ColumnCombinationBitset> expectedUniqueColumnCombinations = fixture.getExpectedBitset(); graph.traverseGraph(); assertThat(graph.getMinimalPositiveColumnCombinations(), IsIterableContainingInAnyOrder .containsInAnyOrder(expectedUniqueColumnCombinations.toArray( new ColumnCombinationBitset[expectedUniqueColumnCombinations.size()]))); }