mock.simpleList.add("qux");
coll.insert(mock);
AggregationBuilder<MockObjectAggregationResult> builder = new AggregationBuilder<MockObjectAggregationResult>();
builder.unwind(new UnwindAggregation("simpleList"))
.group(new GroupAggregation("string").withSum("integer", "integer"));
AggregationResult<MockObjectAggregationResult> aggregationResult = coll.aggregate(builder.build(MockObjectAggregationResult.class));
Assert.assertEquals(1, aggregationResult.results().size());