/// <summary>
/// Gets the value of the specified <see cref="ResultProperty"/> that must be set on the target object.
/// </summary>
/// <param name="request">The request.</param>
/// <param name="resultMap">The result map.</param>
/// <param name="mapping">The mapping.</param>
/// <param name="reader">The reader.</param>
/// <param name="target">The target object</param>
public object Get(RequestScope request, IResultMap resultMap, ResultProperty mapping, ref object target, IDataReader reader)
{
// The property is a IList
IList list = null;
// Get the IList property 获取target类属性mapping.PropertyName的值
object property = ObjectProbe.GetMemberValue(target, mapping.PropertyName,
request.DataExchangeFactory.AccessorFactory);
if (property == null)// Create the list if need
{
property = mapping.ListFactory.CreateInstance(null);
mapping.Set(target, property);
}
list = (IList)property;
object result = null;
//返回的结果中包含其他类对象的情况
IResultMap propertyRresultMap = mapping.NestedResultMap.ResolveSubMap(reader);
if (propertyRresultMap.GroupByProperties.Count > 0)
{
string uniqueKey = GetUniqueKey(propertyRresultMap, reader);
// Gets the [key, result object] already build
IDictionary<string, object> buildObjects = request.GetUniqueKeys(propertyRresultMap);
if (buildObjects != null && buildObjects.ContainsKey(uniqueKey))
{
// Unique key is already known, so get the existing result object and process additional results.
result = buildObjects[uniqueKey];
//In some cases (nested groupings) our object may be null, so there is
//no point in going on
if (result != null)
{
// process resulMapping attribute which point to a groupBy attribute
for (int index = 0; index < propertyRresultMap.Properties.Count; index++)
{
ResultProperty resultProperty = propertyRresultMap.Properties[index];
if (resultProperty.PropertyStrategy is GroupByStrategy)
{
// 跳到PropertyStrategy中的类
resultProperty.PropertyStrategy.Set(request, propertyRresultMap, resultProperty, ref result, reader, null);
}
}
}
result = SKIP;
}
else if (uniqueKey == null || buildObjects == null || !buildObjects.ContainsKey(uniqueKey))
{
// Unique key is NOT known, so create a new result object and then process additional results.
//在ResultMapStrategy类中实现对target类mapping属性的赋值
result = resultMapStrategy.Get(request, resultMap, mapping, ref target, reader);
if (buildObjects == null)
{
buildObjects = new Dictionary<string, object>();
request.SetUniqueKeys(propertyRresultMap, buildObjects);
}
buildObjects[uniqueKey] = result;
}
}
else // Last resultMap have no groupBy attribute
{
if (propertyRresultMap.KeyPropertyNames.Count > 0)
{
result = circularResultMapStrategy.Get(request, resultMap, mapping, ref target, reader);
}
else
{
//在ResultMapStrategy类中实现对target类mapping属性的赋值
result = resultMapStrategy.Get(request, resultMap, mapping, ref target, reader);
}
}
if ((result != null) && (result != SKIP))
{
list.Add(result);
}
return result;
}
/// <summary>
/// Processes the specified <see cref="IDataReader"/>.
/// </summary>
/// <param name="request">The request.</param>
/// <param name="reader">The reader.</param>
/// <param name="resultObject">The result object.</param>
/// <returns>The result object</returns>
public object Process(RequestScope request, ref IDataReader reader, object resultObject)
{
object outObject = resultObject;
//实现对当前CurrentResultMap类中的discrimitor子节点类的设置
IResultMap resultMap = request.CurrentResultMap.ResolveSubMap(reader);
//获取resultMap分组名对应的值
string uniqueKey = GetUniqueKey(resultMap, reader);
// Gets the [key, result object] already build
//根据IResultMap获取对应的IDictionary
IDictionary<string, object> buildObjects = request.GetUniqueKeys(resultMap);
if (buildObjects != null && buildObjects.ContainsKey(uniqueKey))
{
// Unique key is already known, so get the existing result object and process additional results.
outObject = buildObjects[uniqueKey];
// process resulMapping attribute which point to a groupBy attribute
//遍历resultMap.Properties属性中为GroupByStrategy的属性
for (int index = 0; index < resultMap.Properties.Count; index++)
{
ResultProperty resultProperty = resultMap.Properties[index];
if (resultProperty.PropertyStrategy is PropertStrategy.GroupByStrategy)
{
//.................??? 跳到PropertyStrategy中的GroupByStrategy类
resultProperty.PropertyStrategy.Set(request, resultMap, resultProperty, ref outObject, reader, null);
}
}
outObject = SKIP;
}
else if (uniqueKey == null || buildObjects == null || !buildObjects.ContainsKey(uniqueKey))
{
// Unique key is NOT known, so create a new result object and process additional results.
// Fix IBATISNET-241
if (outObject == null)
{
// temp ?, we don't support constructor tag with groupBy attribute
outObject = resultMap.CreateInstanceOfResult(null);//创建返回类的对象
}
for (int index = 0; index < resultMap.Properties.Count; index++)
{
ResultProperty resultProperty = resultMap.Properties[index];
//为当前的resultProperty属性设置其从数据库中读到的值到outObject类中
resultProperty.PropertyStrategy.Set(request, resultMap, resultProperty, ref outObject, reader, null);
}
if (buildObjects == null)
{
buildObjects = new Dictionary<string, object>();
request.SetUniqueKeys(resultMap, buildObjects);
}
buildObjects[uniqueKey] = outObject;
}
return outObject;
}
/// <summary>
/// Processes the specified <see cref="IDataReader"/>.
/// </summary>
/// <param name="request">The request.</param>
/// <param name="reader">The reader.</param>
/// <param name="resultObject">The result object.</param>
/// <returns>The result object</returns>
public object Process(RequestScope request, ref IDataReader reader, object resultObject)
{
object outObject = resultObject;
IResultMap resultMap = request.CurrentResultMap.ResolveSubMap(reader);
string uniqueKey = GetUniqueKey(resultMap, reader);
// Gets the [key, result object] already build
IDictionary<string, object> buildObjects = request.GetUniqueKeys(resultMap);
if (buildObjects != null && buildObjects.ContainsKey(uniqueKey))
{
// Unique key is already known, so get the existing result object and process additional results.
outObject = buildObjects[uniqueKey];
// process resulMapping attribute which point to a groupBy attribute
for (int index = 0; index < resultMap.Properties.Count; index++)
{
ResultProperty resultProperty = resultMap.Properties[index];
if (resultProperty.PropertyStrategy is PropertStrategy.GroupByStrategy)
{
resultProperty.PropertyStrategy.Set(request, resultMap, resultProperty, ref outObject, reader, null);
}
}
outObject = SKIP;
}
else if (uniqueKey == null || buildObjects == null || !buildObjects.ContainsKey(uniqueKey))
{
// Unique key is NOT known, so create a new result object and process additional results.
// Fix IBATISNET-241
if (outObject == null)
{
// temp ?, we don't support constructor tag with groupBy attribute
outObject = resultMap.CreateInstanceOfResult(null);
}
for (int index = 0; index < resultMap.Properties.Count; index++)
{
ResultProperty resultProperty = resultMap.Properties[index];
resultProperty.PropertyStrategy.Set(request, resultMap, resultProperty, ref outObject, reader, null);
}
if (buildObjects == null)
{
buildObjects = new Dictionary<string, object>();
request.SetUniqueKeys(resultMap, buildObjects);
}
buildObjects[uniqueKey] = outObject;
}
return outObject;
}