New example, inheritance/polymorphism

Also move the inheritance example to inheritance/reuse.

6 files changed, 517 insertions, 0 deletions

diff --git a/inheritance/polymorphism/README b/inheritance/polymorphism/README
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+This example shows how to use polymorphism inheritance with ODB. This
+inheritance style is normally used to provide polymorphic behavior through
+a common interface. The base class defines a number of virtual functions and,
+normally, a virtual destructor while the derived classes provide specific
+implementations of these virtual functions.
+
+The other commonly used inheritance style is reuse inheritance. Refer to the
+inheritance/reuse example for more information on this style.
+
+The example consists of the following files:
+
+employee.hxx
+employee.cxx
+  Header and source files defining the 'person' abstract polymorphic
+  persistent class as well as the 'employee' and 'contractor' concrete
+  persistent classes.
+
+employee-odb.hxx
+employee-odb.ixx
+employee-odb.cxx
+employee.sql
+  The first three files contain the database support code and the last file
+  contains the database schema for the employee.hxx header.
+
+  These files are generated by the ODB compiler from employee.hxx using the
+  following command line:
+
+  odb -d <database> --generate-schema --generate-query employee.hxx
+
+  Where <database> stands for the database system we are using, for example,
+  'mysql'.
+
+database.hxx
+  Contains the create_database() function which instantiates the concrete
+  database class corresponding to the database system we are using.
+
+driver.cxx
+  Driver for the example. It includes the employee.hxx and employee-odb.hxx
+  headers to gain access to the persistent classes and their database support
+  code. It also includes database.hxx for the create_database() function
+  declaration.
+
+  In main() the driver first calls create_database() to obtain the database
+  instance. It then persists a number of employee and contractor objects
+  via their common base (person). The next transaction loads these objects,
+  also via their common base. Once loaded, the driver calls the print()
+  virtual function on each of them. Next, the driver changes an employee
+  from temporary to permanent and updates its state in the database, again
+  using the base class interface. The driver then queries the database for
+  all the person objects that have Doe as the last name. The result set of
+  this query contains a mix of employee and contractor objects. The driver
+  iterates over this result set and calls the print() virtual function for
+  each object. Finally, the driver erases the state of the persistent
+  objects from the database, again using the base class interface.
+
+To run the example we may first need to create the database schema (for some
+database systems, such as SQLite, the schema is embedded into the generated
+code which makes this step unnecessary). Using MySQL as an example, this
+can be achieved with the following command:
+
+mysql --user=odb_test --database=odb_test < employee.sql
+
+Here we use 'odb_test' as the database login and also 'odb_test' as the
+database name.
+
+Once the database schema is ready, we can run the example (using MySQL as
+the database):
+
+./driver --user odb_test --database odb_test
diff --git a/inheritance/polymorphism/database.hxx b/inheritance/polymorphism/database.hxx
new file mode 100644
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+++ b/inheritance/polymorphism/database.hxx
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+// file      : inheritance/polymorphism/database.hxx
+// copyright : not copyrighted - public domain
+
+//
+// Create concrete database instance based on the DATABASE_* macros.
+//
+
+#ifndef DATABASE_HXX
+#define DATABASE_HXX
+
+#include <string>
+#include <memory>   // std::auto_ptr
+#include <cstdlib>  // std::exit
+#include <iostream>
+
+#include <odb/database.hxx>
+
+#if defined(DATABASE_MYSQL)
+#  include <odb/mysql/database.hxx>
+#elif defined(DATABASE_SQLITE)
+#  include <odb/connection.hxx>
+#  include <odb/transaction.hxx>
+#  include <odb/schema-catalog.hxx>
+#  include <odb/sqlite/database.hxx>
+#elif defined(DATABASE_PGSQL)
+#  include <odb/pgsql/database.hxx>
+#elif defined(DATABASE_ORACLE)
+#  include <odb/oracle/database.hxx>
+#elif defined(DATABASE_MSSQL)
+#  include <odb/mssql/database.hxx>
+#endif
+
+inline std::auto_ptr<odb::database>
+create_database (int& argc, char* argv[])
+{
+  using namespace std;
+  using namespace odb::core;
+
+  if (argc > 1 && argv[1] == string ("--help"))
+  {
+    cout << "Usage: " << argv[0] << " [options]" << endl
+         << "Options:" << endl;
+
+#if defined(DATABASE_MYSQL)
+    odb::mysql::database::print_usage (cout);
+#elif defined(DATABASE_SQLITE)
+    odb::sqlite::database::print_usage (cout);
+#elif defined(DATABASE_PGSQL)
+    odb::pgsql::database::print_usage (cout);
+#elif defined(DATABASE_ORACLE)
+    odb::oracle::database::print_usage (cout);
+#elif defined(DATABASE_MSSQL)
+    odb::mssql::database::print_usage (cout);
+#endif
+
+    exit (0);
+  }
+
+#if defined(DATABASE_MYSQL)
+  auto_ptr<database> db (new odb::mysql::database (argc, argv));
+#elif defined(DATABASE_SQLITE)
+  auto_ptr<database> db (
+    new odb::sqlite::database (
+      argc, argv, false, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE));
+
+  // Create the database schema. Due to bugs in SQLite foreign key
+  // support for DDL statements, we need to temporarily disable
+  // foreign keys.
+  //
+  {
+    connection_ptr c (db->connection ());
+
+    c->execute ("PRAGMA foreign_keys=OFF");
+
+    transaction t (c->begin ());
+    schema_catalog::create_schema (*db);
+    t.commit ();
+
+    c->execute ("PRAGMA foreign_keys=ON");
+  }
+#elif defined(DATABASE_PGSQL)
+  auto_ptr<database> db (new odb::pgsql::database (argc, argv));
+#elif defined(DATABASE_ORACLE)
+  auto_ptr<database> db (new odb::oracle::database (argc, argv));
+#elif defined(DATABASE_MSSQL)
+  auto_ptr<database> db (new odb::mssql::database (argc, argv));
+#endif
+
+  return db;
+}
+
+#endif // DATABASE_HXX
diff --git a/inheritance/polymorphism/driver.cxx b/inheritance/polymorphism/driver.cxx
new file mode 100644
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+++ b/inheritance/polymorphism/driver.cxx
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+// 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;
+  }
+}
diff --git a/inheritance/polymorphism/employee.cxx b/inheritance/polymorphism/employee.cxx
new file mode 100644
index 0000000..83a51e6
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+++ b/inheritance/polymorphism/employee.cxx
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+// file      : inheritance/polymorphism/employee.cxx
+// copyright : not copyrighted - public domain
+
+#include <iostream>
+
+#include "employee.hxx"
+
+using namespace std;
+
+person::
+~person ()
+{
+}
+
+void employee::
+print ()
+{
+  cout << first_ << ' ' << last_
+       << (temporary_ ? " temporary " : " permanent ")
+       << "employee" << endl;
+}
+
+void contractor::
+print ()
+{
+  cout << first_ << ' ' << last_ << ' ' << email_ << " contractor" << endl;
+}
diff --git a/inheritance/polymorphism/employee.hxx b/inheritance/polymorphism/employee.hxx
new file mode 100644
index 0000000..efb2c1c
--- /dev/null
+++ b/inheritance/polymorphism/employee.hxx
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+// file      : inheritance/polymorphism/employee.hxx
+// copyright : not copyrighted - public domain
+
+#ifndef EMPLOYEE_HXX
+#define EMPLOYEE_HXX
+
+#include <string>
+
+#include <odb/core.hxx>
+
+#pragma db object polymorphic
+class person
+{
+public:
+  person (const std::string& first, const std::string& last)
+      : first_ (first), last_ (last)
+  {
+  }
+
+  const std::string&
+  first () const
+  {
+    return first_;
+  }
+
+  const std::string&
+  last () const
+  {
+    return last_;
+  }
+
+  virtual
+  ~person () = 0;
+
+  virtual void
+  print () = 0;
+
+protected:
+  friend class odb::access;
+  person () {}
+
+  #pragma db id auto
+  unsigned long id_;
+
+  std::string first_;
+  std::string last_;
+};
+
+#pragma db object
+class employee: public person
+{
+public:
+  employee (const std::string& first,
+            const std::string& last,
+            bool temporary)
+      : person (first, last), temporary_ (temporary)
+  {
+  }
+
+  bool
+  temporary () const
+  {
+    return temporary_;
+  }
+
+  void
+  temporary (bool t)
+  {
+    temporary_ = t;
+  }
+
+  virtual void
+  print ();
+
+private:
+  friend class odb::access;
+  employee () {}
+
+  bool temporary_;
+};
+
+#pragma db object
+class contractor: public person
+{
+public:
+  contractor (const std::string& first,
+              const std::string& last,
+              const std::string& email)
+      : person (first, last), email_ (email)
+  {
+  }
+
+  const std::string&
+  email () const
+  {
+    return email_;
+  }
+
+  virtual void
+  print ();
+
+private:
+  friend class odb::access;
+  contractor () {}
+
+  std::string email_;
+};
+
+#endif // EMPLOYEE_HXX
diff --git a/inheritance/polymorphism/makefile b/inheritance/polymorphism/makefile
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--- /dev/null
+++ b/inheritance/polymorphism/makefile
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+# file      : inheritance/polymorphism/makefile
+# copyright : Copyright (c) 2009-2012 Code Synthesis Tools CC
+# license   : GNU GPL v2; see accompanying LICENSE file
+
+include $(dir $(lastword $(MAKEFILE_LIST)))../../build/bootstrap.make
+
+cxx_tun := driver.cxx employee.cxx
+odb_hdr := employee.hxx
+cxx_obj := $(addprefix $(out_base)/,$(cxx_tun:.cxx=.o) $(odb_hdr:.hxx=-odb.o))
+cxx_od  := $(cxx_obj:.o=.o.d)
+
+driver  := $(out_base)/driver
+dist    := $(out_base)/.dist
+test    := $(out_base)/.test
+clean   := $(out_base)/.clean
+
+# Import.
+#
+$(call import,\
+  $(scf_root)/import/odb/stub.make,\
+  odb: odb,odb-rules: odb_rules)
+
+$(call import,\
+  $(scf_root)/import/libodb/stub.make,\
+  l: odb.l,cpp-options: odb.l.cpp-options)
+
+ifdef db_id
+$(call import,\
+  $(scf_root)/import/libodb-$(db_id)/stub.make,\
+  l: odb_db.l,cpp-options: odb_db.l.cpp-options)
+endif
+
+ifeq ($(odb_db.l.cpp-options),)
+odb_db.l.cpp-options := $(out_base)/.unbuildable
+endif
+
+# Build.
+#
+$(driver): $(cxx_obj) $(odb_db.l) $(odb.l)
+$(cxx_obj) $(cxx_od): cpp_options := -I$(out_base) -I$(src_base) -D$(db_macro)
+$(cxx_obj) $(cxx_od): $(odb.l.cpp-options) $(odb_db.l.cpp-options)
+
+genf := $(addprefix $(odb_hdr:.hxx=-odb),.hxx .ixx .cxx) $(odb_hdr:.hxx=.sql)
+gen  := $(addprefix $(out_base)/,$(genf))
+
+$(gen): $(odb)
+$(gen): odb := $(odb)
+$(gen) $(dist): export odb_options += --database $(db_id) --generate-schema \
+--generate-query --table-prefix inh_poly_
+$(gen): cpp_options := -I$(src_base)
+$(gen): $(odb.l.cpp-options)
+
+$(call include-dep,$(cxx_od),$(cxx_obj),$(gen))
+
+# Alias for default target.
+#
+$(out_base)/: $(driver)
+
+# Dist
+#
+name := $(subst /,-,$(subst $(src_root)/,,$(src_base)))
+
+$(dist): db_id := @database@
+$(dist): sources := $(cxx_tun)
+$(dist): headers := $(odb_hdr)
+$(dist): export name := $(name)
+$(dist): export odb_header_stem := $(basename $(odb_hdr))
+$(dist): export extra_dist := README $(call vc9projs,$(name)) \
+$(call vc10projs,$(name))
+$(dist):
+	$(call dist-data,$(sources) $(headers) README database.hxx)
+	$(call meta-automake,../template/Makefile.am)
+	$(call meta-vc9projs,../template/template,$(name))
+	$(call meta-vc10projs,../template/template,$(name))
+
+# Test.
+#
+$(test): header := $(odb_hdr)
+$(test): $(driver)
+	$(call schema)
+	$(call message,test $<,$< --options-file $(dcf_root)/db.options)
+
+# Clean.
+#
+$(clean):                            \
+  $(driver).o.clean                  \
+  $(addsuffix .cxx.clean,$(cxx_obj)) \
+  $(addsuffix .cxx.clean,$(cxx_od))  \
+  $(addprefix $(out_base)/,$(odb_hdr:.hxx=-odb.cxx.hxx.clean))
+
+# Generated .gitignore.
+#
+ifeq ($(out_base),$(src_base))
+$(driver): | $(out_base)/.gitignore
+
+$(out_base)/.gitignore: files := driver $(genf)
+$(clean): $(out_base)/.gitignore.clean
+
+$(call include,$(bld_root)/git/gitignore.make)
+endif
+
+# How to.
+#
+$(call include,$(bld_root)/dist.make)
+$(call include,$(bld_root)/meta/vc9proj.make)
+$(call include,$(bld_root)/meta/vc10proj.make)
+$(call include,$(bld_root)/meta/automake.make)
+
+$(call include,$(bld_root)/cxx/standard.make) # cxx_standard
+ifdef cxx_standard
+$(gen): odb_options += --std $(cxx_standard)
+$(call include,$(odb_rules))
+endif
+
+$(call include,$(bld_root)/cxx/cxx-d.make)
+$(call include,$(bld_root)/cxx/cxx-o.make)
+$(call include,$(bld_root)/cxx/o-e.make)
+