Oracle Coherence for C++ API
Release 3.7.1.0

E22845-01

ReflectionExtractor Class Reference

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

Inherits AbstractExtractor.

Inherited by TypedExtractor, and TypedExtractor< RH::ValueType::BoxedType, C, M, coherence::lang::BoxHandle< RH::ValueType >, OH >.

List of all members.


Detailed Description

Reflection-based ValueExtractor implementation.

Local execution of a ReflectionExtractor is dependent upon target class and method having been registered with the SystemClassLoader. For cases where the registration has not been performed or is not possible locally executable C++ extractors may either be custom built, or auto-generated using the TypedExtractor<>.

Author:
djl/mf 2008.03.06
See also:
ChainedExtractor

TypedExtractor

Method

 

Public Types

typedef spec::Handle Handle
 ReflectionExtractor Handle definition.
typedef spec::View View
 ReflectionExtractor View definition.
typedef spec::Holder Holder
 ReflectionExtractor 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
virtual void readExternal (PofReader::Handle hIn)
  
virtual void writeExternal (PofWriter::Handle hOut) const
  
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
virtual String::View getMethodName () const
 Determine the name of the method that this extractor is configured to invoke.
virtual ObjectArray::View getParameters () const
 Return the array of arguments used to invoke the method.

Protected Member Functions

 ReflectionExtractor ()
 Construct an empty ReflectionExtractor (necessary for the PortableObject interface).
 ReflectionExtractor (String::View vsMethod, ObjectArray::View vaParam=NULL, int32_t nTarget=value)
 Construct a ReflectionExtractor based on a method name, optional parameters and the entry extraction target.
 ReflectionExtractor (const ReflectionExtractor &that)
 Copy constructor.

Protected Attributes

MemberView< Stringm_vsMethod
 The name of the method to invoke.
MemberView< ObjectArraym_vaParam
 The parameter array.
MemberView< Methodm_vMethod
 The resolved Method.

Constructor & Destructor Documentation

ReflectionExtractor ( String::View  vsMethod,
    ObjectArray::View  vaParam = NULL,
    int32_t  nTarget = value 
  )    [protected]

Construct a ReflectionExtractor based on a method name, optional parameters and the entry extraction target.

Parameters:
 vsMethod the name of the method to invoke via reflection
 vaParam the array of arguments to be used in the method invocation; may be NULL
 nTarget one of the value or key values
Since:
Coherence 3.5


Member Function Documentation

virtual String::View getMethodName (  )  const [virtual]

Determine the name of the method that this extractor is configured to invoke.

Returns:
the name of the method to invoke using reflection

virtual ObjectArray::View getParameters (  )  const [virtual]

Return the array of arguments used to invoke the method.

Returns:
the array of arguments used to invoke the method


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