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Updating Your Objects - C++

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Namescopes

Name scopes are designed primarily for individual lookup; you can find a named object by looking up its name in the scope of the appropriate scope object.

carObj.nameObj(cont, "Car");
//name the object in the scope of the cont
//where cont is the handle to the container
carObj.lookupObj(cont, "Car");
//to look up and assign to the carObj the object named "Car" in the cont scope


objects.ddl

class Car : ooObj
{  
public:
    int VIN;
    void setVin(int vinNum)
    {
        ooUpdate();
        VIN = vinNum;
    }
    int returnVin()
    {
        return VIN;
    }
};

class Part : ooObj
{
public:
    int partNum;
    void setPartNum(int num)
    {
        ooUpdate();
        partNum = num;
    }
    int returnPartNum()
    {
        return partNum;
    }
};

createObj.cpp

#include <iostream>
using namespace std;
#include <ooObjy.h>
#include "objects.h"

int main(int argc, char* argv[])
{
  int returnval = 0;
  ooObjy::startup();
  char *bootfile = "test.boot";
  char *dbName = "testDB";
  char *contName = "testCont";

  ooConnection *connection = ooObjy::getConnection(bootfile);

  ooSession *session = connection->createSession("main_session");

  try
  {

    session->begin(oocUpdate);

    ooHandle(ooFDObj) fd;
    fd.exist(bootfile, oocUpdate);

    ooHandle(ooDBObj) db;
    if (db.exist(fd, dbName));
    else
    {
      db = new ooDBObj(dbName);
    }

    ooHandle(ooContObj) cont;
    if (cont.exist(db, contName, oocUpdate));
    else
    {
      cont = new(db, 4, 0, contName) ooContObj;
    }

    ooHandle(Car) carObj;
    carObj = new(cont) Car();
    carObj.nameObj(cont, "Car"); //name object "Car" in scope of cont

    session->commit();
  }

  catch(ooException &error)
  {
    cerr << error.what() << endl;
    session->abort();
    returnval = 1;
  }

  catch(...)
  {
    cerr << "unknown error" << endl;
    session->abort();
    returnval = 1;
  }

  ooObjy::shutdown();
  return returnval;
}



Updating an Object

To update an object, you call the functions from the object handle.

ooHandle(Car) carObj; //declare object handle
carObj = ... //instantiate car handle
carObj->setVin(); //call function from handle



Using the database created from the example above, you can lookup an object and update it.

update.cpp

#include <iostream>
using namespace std;
#include <ooObjy.h>
#include "objects.h"

int main(int argc, char* argv[])
{
  int returnval = 0;

  ooObjy::startup();
  char *bootfile = "test.boot";
  char *dbName = "testDB";
  char *contName = "testCont";

  ooConnection *connection = ooObjy::getConnection(bootfile);

  ooSession *session = connection->createSession("main_session");

  try
  {

    session->begin(oocUpdate);

    ooHandle(ooFDObj) fd;
    fd.exist(bootfile, oocUpdate);

    ooHandle(ooDBObj) db;
    if (db.exist(fd, dbName));
    else
    {
      db = new ooDBObj(dbName);
    }

    ooHandle(ooContObj) cont;
    if (cont.exist(db, contName, oocUpdate));
    else
    {
      cont = new(db, 4, 0, contName) ooContObj;
    }

    ooHandle(Car) obj;
	obj.lookupObj(cont, "Car");
	carObj->setVin(23);
	session->commit();
  }

  catch(ooException &error)
  {
    cerr << error.what() << endl;
    session->abort();
    returnval = 1;
  }

  catch(...)
  {
    cerr << "unknown error" << endl;
    session->abort();
    returnval = 1;
  }

  ooObjy::shutdown();
  return returnval;
}



Deleting an Object

To delete an object, you call the ooDelete function and pass in the object handle.

ooDelete(obj);
//where obj is the handle to the object you're deleting
//obj can be handle to a database, container, or an object



Using the database created from the example above, you can lookup an object and delete it.

update.cpp

#include <iostream>
using namespace std;
#include <ooObjy.h>
#include "objects.h"

int main(int argc, char* argv[])
{
  int returnval = 0;

  ooObjy::startup();
  char *bootfile = "test.boot";
  char *dbName = "testDB";
  char *contName = "testCont";

  ooConnection *connection = ooObjy::getConnection(bootfile);

  ooSession *session = connection->createSession("main_session");

  try
  {

    session->begin(oocUpdate);

    ooHandle(ooFDObj) fd;
    fd.exist(bootfile, oocUpdate);

    ooHandle(ooDBObj) db;
    if (db.exist(fd, dbName));
    else
    {
      db = new ooDBObj(dbName);
    }

    ooHandle(ooContObj) cont;
    if (cont.exist(db, contName, oocUpdate));
    else
    {
      cont = new(db, 4, 0, contName) ooContObj;
    }

    ooHandle(Car) obj;
	obj.lookupObj(cont, "Car");
	ooDelete(carObj)
	session->commit();
  }

  catch(ooException &error)
  {
    cerr << error.what() << endl;
    session->abort();
    returnval = 1;
  }

  catch(...)
  {
    cerr << "unknown error" << endl;
    session->abort();
    returnval = 1;
  }

  ooObjy::shutdown();
  return returnval;
}