/// <summary>
/// 使用主键批量获取对象集合。
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="session"></param>
/// <param name="ids"></param>
/// <returns></returns>
public static IList <T> GetList <T>(this ISession session, IEnumerable ids)
{
CacheLoader loader = new CacheLoader();
var entityPersister = session.GetSessionImplementation().GetEntityPersister(typeof(T).FullName, null);
var entityName = typeof(T).FullName;
var eventSource = (IEventSource)session;
var loadType = LoadEventListener.Get;
List <T> output = new List <T>();
ArrayList missings = new ArrayList();
foreach (object id in ids)
{
EntityKey entityKey = new EntityKey(id, entityPersister, EntityMode.Poco);
LoadEvent loadEvent = new LoadEvent(id, entityName, false, eventSource);
var entity = loader.LoadFromSessionCache(loadEvent, entityKey, loadType);
if (entity == null)
{
entity = loader.LoadFromSecondLevelCache(loadEvent, entityPersister, loadType);
}
if (entity != null)
{
output.Add((T)entity);
}
else
{
missings.Add(id);
}
}
if (missings.Count > 0)
{
//对组合键进行处理
if (entityPersister.IdentifierType.IsComponentType)
{
ComponentType idType = (ComponentType)entityPersister.IdentifierType;
List <HashSet <object> > props = new List <HashSet <object> >();
foreach (string name in idType.PropertyNames)
{
props.Add(new HashSet <object>());
}
foreach (var missing in missings)
{
var values = idType.GetPropertyValues(missing, EntityMode.Poco);
for (int i = 0; i < values.Length; i++)
{
props[i].Add(values[i]);
}
}
var cr = session.CreateCriteria(entityName);
//合并为查询
int index = 0;
foreach (HashSet <object> set in props)
{
string propName = entityPersister.IdentifierPropertyName + "." + idType.PropertyNames[index];
if (set.Count == 1)
{
cr = cr.Add(Expression.Eq(propName, set.First()));
}
else
{
cr = cr.Add(Expression.In(propName, set.ToArray()));
}
index++;
}
output.AddRange(cr.List <T>());
}
else
{
output.AddRange(session.CreateCriteria(entityName)
.Add(Expression.In(entityPersister.IdentifierPropertyName, missings))
.List <T>());
}
}
return(output);
}
