/// <summary>
/// Aggregate the results of the parallel aggregations.
/// </summary>
/// <param name="results">
/// Results to aggregate.
/// </param>
/// <returns>
/// The aggregation of the parallel aggregation results.
/// </returns>
public virtual object AggregateResults(ICollection results)
{
IParallelAwareAggregator aggregator = (IParallelAwareAggregator)m_aggregator;
IDictionary dictionaryResult = new HashDictionary();
foreach (IDictionary dictPart in results)
{
// partial aggregation results are maps with distinct values
// as keys and partial aggregation results as values
foreach (DictionaryEntry entry in dictPart)
{
object distinct = entry.Key;
object result = entry.Value;
// collect all the aggregation results per group
ICollection group = (ICollection)dictionaryResult[distinct];
if (group == null)
{
dictionaryResult.Add(distinct, group = new ArrayList());
}
CollectionUtils.Add(group, result);
}
}
IDictionary newResult = new HashDictionary(dictionaryResult);
if (dictionaryResult.Count == 0)
{
// we need to call "AggregateResults" on the underlying
// aggregator to fulfill our contract, even though any result
// will be discarded
aggregator.AggregateResults(NullImplementation.GetCollection());
}
else
{
IFilter filter = m_filter;
foreach (DictionaryEntry entry in dictionaryResult)
{
ICollection group = (ICollection)entry.Value;
object result = aggregator.AggregateResults(group);
if (filter == null || filter.Evaluate(result))
{
newResult[entry.Key] = result;
}
else
{
newResult.Remove(entry.Key);
}
}
}
return(newResult);
}
/// <summary>
/// Obtain the result of the aggregation.
/// </summary>
/// <remarks>
/// If the <paramref name="isFinal"/> parameter is <b>true</b>, the
/// returned object must be the final result of the aggregation;
/// otherwise, the returned object will be treated as a partial
/// result that should be incorporated into the final result.
/// </remarks>
/// <param name="isFinal">
/// <b>true</b> to indicate that the final result of the aggregation
/// process should be returned; this will only be <b>false</b> if a
/// parallel approach is being used.
/// </param>
/// <returns>
/// The result of the aggregation process.
/// </returns>
protected override object FinalizeResult(bool isFinal)
{
ICollection coll = m_coll;
m_coll = null; // COHNET-181
if (isFinal)
{
// return the final aggregated result
return(coll == null?NullImplementation.GetCollection() : coll);
}
else
{
// return partial aggregation data
return(coll);
}
}
protected void DoTestTopN(string sCache)
{
INamedCache cache = CacheFactory.GetCache(sCache);
cache.Clear();
TopNAggregator agent = new TopNAggregator(
IdentityExtractor.Instance, SafeComparer.Instance, 10);
object[] aoEmpty = new Object[0];
object[] aoResult;
aoResult = (object[])cache.Aggregate(
NullImplementation.GetCollection(), agent);
AssertArrayEquals(aoEmpty, aoResult, "null collection");
aoResult = (object[])cache.Aggregate(
new ArrayList(new object[] { "1" }), agent);
AssertArrayEquals(aoEmpty, aoResult, "singleton collection");
aoResult = (object[])cache.Aggregate((IFilter)null, agent);
AssertArrayEquals(aoEmpty, aoResult, "null filter");
aoResult = (object[])cache.Aggregate(AlwaysFilter.Instance, agent);
AssertArrayEquals(aoEmpty, aoResult, "AlwaysFilter");
Hashtable ht = new Hashtable();
int cKeys = 10000;
for (int i = 1; i <= cKeys; i++)
{
ht.Add(i.ToString(), i);
}
cache.InsertAll(ht);
object[] aoTop10 = new object[10];
for (int i = 0; i < 10; i++)
{
aoTop10[i] = cKeys - i;
}
aoResult = (object[])cache.Aggregate(
NullImplementation.GetCollection(), agent);
AssertArrayEquals(aoEmpty, aoResult);
aoResult = (object[])cache.Aggregate(
new ArrayList(new object[] { "1" }), agent);
AssertArrayEquals(new object[] { 1 }, aoResult);
aoResult = (object[])cache.Aggregate(
new ArrayList(new object[] { "1" }), agent);
AssertArrayEquals(new object[] { 1 }, aoResult);
aoResult = (object[])cache.Aggregate((IFilter)null, agent);
AssertArrayEquals(aoTop10, aoResult);
aoResult = (object[])cache.Aggregate(AlwaysFilter.Instance, agent);
AssertArrayEquals(aoTop10, aoResult);
// test duplicate values
cache.Clear();
cKeys = 100;
ht = new Hashtable(cKeys);
for (int i = 1; i <= cKeys; ++i)
{
ht.Add(i.ToString(), i / 2);
}
cache.InsertAll(ht);
aoTop10 = new object[10];
for (int i = 0; i < 10; ++i)
{
aoTop10[i] = (cKeys - i) / 2;
}
aoResult = (object[])cache.Aggregate((IFilter)null, agent);
AssertArrayEquals(aoTop10, aoResult);
CacheFactory.Shutdown();
}