Oracle Coherence for C++ API


TypedExtractor Class Template Reference

#include <coherence/util/extractor/TypedExtractor.hpp>

Inherits ReflectionExtractor.

Inherited by BoxExtractor.

List of all members.

Detailed Description

template<class R, class C, R(C::*)() const M, class RH = Object::Holder, class OH = typename C::Holder>
class coherence::util::extractor::TypedExtractor< R, C, M, RH, OH >

Template based ValueExtractor implementation.

This extractor functions on const methods which return Objects, for an extractor which works with non-Object return types see BoxExtractor.

For ease of use the COH_TYPED_EXTRACTOR macro can be used to easily construct an instance of this class. For example the following constructs an extractor for calling the "String::View Address::getState() const" method.

 ValueExtractor::View vExt = COH_TYPED_EXTRACTOR(String::View, Address, getState);
mf 2009.03.20
See also:

Public Types

typedef spec::Handle  Handle
  TypedExtractor<R, C, M, RH, OH> Handle definition.
typedef spec::View  View
  TypedExtractor<R, C, M, RH, OH> View definition.
typedef spec::Holder  Holder
  TypedExtractor<R, C, M, RH, OH> Holder definition.

Public Member Functions

virtual Object::Holder  extract (Object::Holder ohTarget) const
  Extract the value from the passed object.

The returned value may be NULL.

ohTarget  an Object to retrieve the value from
the extracted value; NULL is an acceptable value
ClassCastException  if this ValueExtractor is incompatible with the passed object to extract a value from and the implementation requires the passed object to be of a certain type
Exception  if this ValueExtractor encounters an exception in the course of extracting the value
IllegalArgumentException  if this ValueExtractor cannot handle the passed object for any other reason; an implementor should include a descriptive message
UnsupportedOperationException  always

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 hashCode is:

  • Whenever it is invoked on the same Object more than once during an execution of an application, the hashCode method must consistently return the same value, provided no information used in equals comparisons on the object is modified. This value need not remain consistent from one execution of an application to another execution of the same application.
  • If two Objects are equal according to the equals method, then calling the hashCode method on each of the two Objects must produce the same value.
  • It is not required that if two Objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct results. However, the programmer should be aware that producing distinct results for unequal objects may improve the performance of hash-based containers.

The default implementation is identity based.

a hash code value for this Object

virtual void  toStream (std::ostream &out) const
  Output a human-readable description of this Object to the given stream.

coherence::lang::operator<<(std::ostream, Object::View) is defined and will call into the toStream 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.

 Object::View vKey   = ...
 Object::View vValue = ...
 std::cout << vKey << " = " << vValue << std::endl;

 String::Handle hs = COH_TO_STRING(vKey << " = " << vValue);
out  the stream used to output the description

Protected Member Functions

  TypedExtractor ()
  Construct a TypedExtractor.
  TypedExtractor (String::View vsMethod)
  Construct a TypedExtractor based on a method name and optional parameters.

Constructor & Destructor Documentation

TypedExtractor ( String::View  vsMethod  )  [inline, protected]

Construct a TypedExtractor based on a method name and optional parameters.

The method name is only used for the purposes of serializing the extractor for execution on remote Java members.

vsMethod  the name of the method to invoke via reflection

The documentation for this class was generated from the following file:
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