#include <coherence/util/filter/ValueChangeEventFilter.hpp>
Inherits ExtractorFilter.
This filter evaluates to true only for update events that change the value of an extracted attribute.
Example: a filter that evaluates to true if there is an update to an Employee object that changes a value of the LastName property.
ValueChangeEventFilter::create(ReflectionExtractor::create("LastName"));
see MapEventFilter
Public Types | ||||
typedef spec::Handle | Handle | |||
ValueChangeEventFilter Handle definition. | ||||
typedef spec::View | View | |||
ValueChangeEventFilter View definition. | ||||
typedef spec::Holder | Holder | |||
ValueChangeEventFilter Holder definition. | ||||
Public Member Functions | ||||
virtual bool | evaluate (Object::View v) const | |||
Apply the test to the object.
| ||||
virtual bool | equals (Object::View v) const | |||
virtual size32_t | hashCode () const | |||
Return a hash code value for the Object. This method is supported for the benefit of hash-based containers.
The general contract of
The default implementation is identity based.
| ||||
virtual TypedHandle < const String > | toString () const | |||
Output a human-readable description of this Object to the given stream. Note that when overriding this method the return type must be TypedHandle<const String> rather then String::View. These two types are assignment compatible but not equivalent and declaring the override with String::View will not be a compatible override. coherence::lang::operator<<(std::ostream, Object::View) is defined and will call into the toString method, to output Objects. If a managed String object is desired, the COH_TO_STRING macro can be used to build up a String from streamable contents and is generally how toString() will be implemented.
Object::View vKey = ... Object::View vValue = ... std::cout << vKey << " = " << vValue << std::endl; String::View vs = COH_TO_STRING(vKey << " = " << vValue); The COH_TO_STRING macro is also the most common way to implement the toString method. For example:
virtual TypedHandle<const String> Person::toString() const { return COH_TO_STRING("Name: " << f_sName << " SSN: " << f_nSSN); }
| ||||
Protected Member Functions | ||||
ValueChangeEventFilter () | ||||
Default constructor (necessary for the PortableObject interface). | ||||
ValueChangeEventFilter (ValueExtractor::View vValueExtractor) | ||||
Construct a ValueChangeEventFilter that evaluates MapEvent values based on the specified extractor. | ||||
virtual bool | evaluateExtracted (Object::View vExtracted) const | |||
Evaluate the specified extracted value. |
ValueChangeEventFilter | ( | ValueExtractor::View | vValueExtractor | ) | [protected] |
Construct a ValueChangeEventFilter that evaluates MapEvent values based on the specified extractor.
vExtractor | ValueExtractor to extract MapEvent values |
virtual bool evaluateExtracted | ( | Object::View | vExtracted | ) | const [protected, virtual] |
Evaluate the specified extracted value.
vExtracted | an extracted value to evaluate |
Implements ExtractorFilter.