ComparisonValueExtractor Class |
14c (14.1.1.0)
F23534-02
A synthetic IValueExtractor that returns a result of
comparison between two values extracted from the same target.
Inheritance HierarchySystemObject
Tangosol.Util.ExtractorAbstractExtractor
Tangosol.Util.ExtractorAbstractCompositeExtractor
Tangosol.Util.ExtractorComparisonValueExtractor
Tangosol.Util.ExtractorAbstractExtractor
Tangosol.Util.ExtractorAbstractCompositeExtractor
Tangosol.Util.ExtractorComparisonValueExtractor
Namespace: Tangosol.Util.Extractor
Assembly: Coherence (in Coherence.dll) Version: 14.1.1.14 (14.1.1.14)
SyntaxC#
public class ComparisonValueExtractor : AbstractCompositeExtractor
The ComparisonValueExtractor type exposes the following members.
Constructors| Name | Description | |
|---|---|---|
 | ComparisonValueExtractor |
Default constructor.
|
| ComparisonValueExtractor(IValueExtractor) |
Construct a ComparisonValueExtractor based on a specified
IValueExtractor array.
|
| ComparisonValueExtractor(String, String) |
Construct a ComparisonValueExtractor based on two member
names.
|
| ComparisonValueExtractor(IValueExtractor, IValueExtractor) |
Construct a ComparisonValueExtractor based on two specified
extractors.
|
| ComparisonValueExtractor(String, String, IComparer) |
Construct a ComparisonValueExtractor based on two method
names and a IComparer object.
|
| ComparisonValueExtractor(IValueExtractor, IValueExtractor, IComparer) |
Construct a ComparisonValueExtractor based on two specified
extractors and a IComparer object.
|
Properties| Name | Description | |
|---|---|---|
 | Comparer |
Return an IComparer used by this extractor.
|
| Extractors |
Obtain the IValueExtractor array.
(Inherited from AbstractCompositeExtractor.) |
| Target |
The target of the extractor.
(Inherited from AbstractExtractor.) |
Methods| Name | Description | |
|---|---|---|
| Compare |
Compares its two arguments for order.
(Inherited from AbstractExtractor.) |
| CompareEntries |
Compare two entries.
(Inherited from AbstractExtractor.) |
| Equals |
Compare the AbstractCompositeExtractor with another object
to determine equality.
(Inherited from AbstractCompositeExtractor.) |
| Extract |
Extract the value from the passed object.
(Overrides AbstractExtractorExtract(Object).) |
| ExtractFromEntry |
Extract the value from the passed Entry object. The returned
value should follow the conventions outlined in the
Extract(Object) method.
(Inherited from AbstractExtractor.) |
| ExtractOriginalFromEntry |
Extract the value from the "original value" of the passed
CacheEntry object or the key (if targeted). This method's conventions are exactly the same
as the ExtractFromEntry(ICacheEntry) method.
(Inherited from AbstractExtractor.) |
 | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
| GetHashCode |
Determine a hash value for the AbstractCompositeExtractor object
according to the general object.GetHashCode contract.
(Inherited from AbstractCompositeExtractor.) |
 | GetStreamFormat |
Select an optimal stream format to use to store the passed object
in a stream.
|
| GetType | Gets the Type of the current instance. (Inherited from Object.) |
| MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
| ReadExternal |
Restore the contents of a user type instance by reading its state
using the specified IPofReader object.
(Overrides AbstractCompositeExtractorReadExternal(IPofReader).) |
| ToString |
Return a human-readable description for this
IValueExtractor.
(Inherited from AbstractCompositeExtractor.) |
| WriteExternal |
Save the contents of a POF user type instance by writing its
state using the specified IPofWriter object.
(Overrides AbstractCompositeExtractorWriteExternal(IPofWriter).) |
Fields| Name | Description | |
|---|---|---|
 | m_comparer |
An underlying IComparer object (optional).
|
| m_extractors |
The IValueExtractor array.
(Inherited from AbstractCompositeExtractor.) |
| m_target |
Specifies which part of the entry should be used by the
ExtractFromEntry(ICacheEntry) operation. Legal values are
VALUE (default) or KEY.
(Inherited from AbstractExtractor.) |
RemarksIn a most general case, the extracted value represents an integer value calculated accordingly to the contract of CompareTo(Object) or Compare(Object, Object) methods. However, in more specific cases, when the compared values are of common numeric type, the ComparisonValueExtractor will return a numeric difference between those values. The .NET type of the comparing values will dictate the .NET type of the result.
For example, lets assume that a cache contains business objects that have two properties: SellPrice and BuyPrice (both double). Then, to query for all objects that have SellPrice less than BuyPrice we would use the following:
ValueExtractor extractDiff = new ComparisonValueExtractor( new ReflectionExtractor("SellPrice"), new ReflectionExtractor("BuyPrice")); Filter filter = new LessFilter(extractDiff, 0.0); ICollection entries = cache.GetEntries(filter);
See Also