New example, inheritance/polymorphism

Also move the inheritance example to inheritance/reuse.

1 files changed, 102 insertions, 0 deletions

diff --git a/inheritance/polymorphism/driver.cxx b/inheritance/polymorphism/driver.cxx
new file mode 100644
index 0000000..e0c9952
--- /dev/null
+++ b/inheritance/polymorphism/driver.cxx
@@ -0,0 +1,102 @@
+// file      : inheritance/polymorphism/driver.cxx
+// copyright : not copyrighted - public domain
+
+#include <memory>   // std::auto_ptr
+#include <iostream>
+
+#include <odb/database.hxx>
+#include <odb/transaction.hxx>
+
+#include "database.hxx" // create_database
+
+#include "employee.hxx"
+#include "employee-odb.hxx"
+
+using namespace std;
+using namespace odb::core;
+
+int
+main (int argc, char* argv[])
+{
+  try
+  {
+    auto_ptr<database> db (create_database (argc, argv));
+
+    unsigned long id1, id2;
+
+    // Add a few employee and contractor objects to the database.
+    //
+    {
+      auto_ptr<person> p1 (new employee ("John", "Doe", true));
+      auto_ptr<person> p2 (new contractor ("Jane", "Doe", "jane@doe.com"));
+
+      transaction t (db->begin ());
+      id1 = db->persist (*p1); // Stores employee.
+      id2 = db->persist (*p2); // Stores contractor.
+      t.commit ();
+    }
+
+    // Load polymorphic objects given their object ids.
+    //
+    {
+      transaction t (db->begin ());
+      auto_ptr<person> p1 (db->load<person> (id1)); // Loads employee.
+      auto_ptr<person> p2 (db->load<person> (id2)); // Loads contractor.
+      t.commit ();
+
+      p1->print ();
+      p2->print ();
+    }
+
+    // Make John Doe a permanent employee.
+    //
+    {
+      transaction t (db->begin ());
+
+      auto_ptr<employee> e (db->load<employee> (id1));
+      e->temporary (false);
+      person& p (*e);
+      db->update (p); // Updates employee.
+
+      t.commit ();
+    }
+
+    // Query all the person objects that have Doe as the last name.
+    //
+    {
+      typedef odb::query<person> query;
+      typedef odb::result<person> result;
+
+      transaction t (db->begin ());
+
+      result r (db->query<person> (query::last == "Doe"));
+
+      for (result::iterator i (r.begin ()); i != r.end (); ++i)
+      {
+        // We can check the discriminator before loading the object.
+        //
+        string d (i.discriminator ());
+        cout << "discriminator: " << d << endl;
+
+        i->print (); // Can be employee or contractor.
+      }
+
+      t.commit ();
+    }
+
+    // Erase the objects from the database.
+    //
+    {
+      transaction t (db->begin ());
+      auto_ptr<person> p (db->load<person> (id1)); // Loads employee.
+      db->erase (*p);                              // Erases employee.
+      db->erase<person> (id2);                     // Erases contractor.
+      t.commit ();
+    }
+  }
+  catch (const odb::exception& e)
+  {
+    cerr << e.what () << endl;
+    return 1;
+  }
+}