HP Integrity NonStop J-Series - Manual (Page 160)

RWCollectableString dummy("Mary"); //10
RWCollectable* t = sc.find( &dummy ); //11
if(t){ //12
if(t->isA() == dummy.isA()) //13
cout << *(RWCollectableString*)t << "\n"; //14
}
else
cout << "Object not found.\n"; //15
cout << sc.occurrencesOf(&dummy) << "\n"; //16
sc.clearAndDestroy();
return 0;
}
Program Output:
5
Mary
2
Here's the line-by-line description:
//1 - //7 These lines are from the example in Chapter 13.
//8 Insert another instance with the value Mary.
//9 This statement prints out 5, the total number of entries in the sorted collection.
//10 A throwaway variable dummy is constructed, to be used to test for the occurrences of
strings containing Mary.
//11 The collection is asked to return a pointer to the first object encountered that compares
equal to the argument. A nil pointer (zero) is returned if there is no such object.
//12 The pointer is tested to make sure it is not nil.
//13 Paranoid check. In this example, it is obvious that the items in the collection must be of
type
RWCollectableString . In general, it may not be obvious.
//14 Because of the results of step 13, the cast to an RWCollectableString pointer is safe. The
pointer is then dereferenced and printed.
//15 If the pointer t was nil, then an error message would have been printed here.
//16 The call to occurrencesOf() returns the number of items that compare equal to its
argument. In this case, two items are found, the two occurrences of Mary.