usedatabase2.cpp

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//: C09:UseDatabase2.cpp
// From "Thinking in C++, Volume 2", by Bruce Eckel & Chuck Allison.
// (c) 1995-2004 MindView, Inc. All Rights Reserved.
// See source code use permissions stated in the file 'License.txt',
// distributed with the code package available at www.MindView.net.
// Tests the Countable "mixin" class.
#include <cassert>
#include "DBConnection.h"

class DBClient {
  DBConnection* db;
public:
  DBClient(DBConnection* dbCon) {
    db = dbCon;
    db->attach();
  }
  ~DBClient() { db->detach(); }
  // Other database requests using db...
};

int main() {
  DBConnection* db = DBConnection::create("MyDatabase");
  assert(db->refCount() == 1);
  DBClient c1(db);
  assert(db->refCount() == 2);
  DBClient c2(db);
  assert(db->refCount() == 3);
  // Use database, then release attach from original create
  db->detach();
  assert(db->refCount() == 2);
} ///:~