Oracle® Fusion Middleware C++ API Reference for Oracle Coherence
12c (12.2.1.3.0)
E80355-01
coherence::util::SortedBag::WrapperComparator

SortedBag::WrapperComparator Class Reference

#include <coherence/util/SortedBag.hpp>

Inherits Object, and Comparator.

List of all members.

Detailed Description

WrapperComparator is a Comparator implementation that is aware of UniqueElement wrappers and will delegate the comparison of the elements in both forms to the wrapped comparator.

Public Types

typedef spec::Handle Handle
 WrapperComparator Handle definition.
typedef spec::View View
 WrapperComparator View definition.
typedef spec::Holder Holder
 WrapperComparator Holder definition.

Public Member Functions

virtual int32_t compare (Object::View v1, Object::View v2) const
 Compare two Objects.

If both Objects are comparable with this Comparator, return < 0, 0 or > 0 if the first Object is less than, equal to, or greater than the second Object.

The general contract for this method is:

  1. If either of two handles are NULL, a coherence::lang::NullPointerException shall be thrown;
  2. If either of two Objects are not comparable with this Comparator, a coherence::lang::IllegalArgumentException shall be thrown;
  3. It shall be consistent with the Object::equals() relation, i.e. compare(v1, v2) == 0 if and only if Object::equals(v1, v2) == true
  4. The subsequent calls to this method shall return the same value until either of arguments changed
  5. It shall be anti-symmetric, i.e. compare(v1, v2) == -compare(v2, v1)

A typical implementation of Comparator may look as follows: 

 int32_t MyTypeComparator::compare(Object::View v1,
                                   Object::View v2) const
     {
     // compares instances of class MyType only
     if (!v1 || !v2)
         {
         COH_THROW(NullPointerException());
         }
     MyType::View vTypedObj1 = cast<MyType::View>(v1);
     MyType::View vTypedObj2 = cast<MyType::View>(v2);
     if (!vTypedObj1 || !vTypedObj1)
         {
         COH_THROW(IllegalArgumentException("Instances of MyType expected"));
         }
     // here we suppose that the state of the MyType is defined by
     // single field of integer type
     if (vTypedObj1->m_intField == vTypedObj2->m_intField)
         {
         return 0;
         }
     else if (vTypedObj1->m_intField < vTypedObj2->m_intField)
         {
         return -1;
         }
     else
         {
         return 1;
         }
     }


Protected Attributes

FinalView< Comparator > f_vComparator
 The underlying "logical" comparator.
The documentation for this class was generated from the following file:
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