Oracle Coherence for C++ API
Release 3.7.0.0

E18684-01

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);

Author:
mf 2009.03.20
See also:
BoxExtractor

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.

Parameters:
ohTarget an Object to retrieve the value from
Returns:
the extracted value; NULL is an acceptable value
Exceptions:
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

Exceptions:
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.

Returns:
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);

Parameters:
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.

Parameters:
vsMethod the name of the method to invoke via reflection


The documentation for this class was generated from the following file:
Copyright © 2000, 2011, Oracle and/or its affiliates. All rights reserved.