PObject Class

OCCI provides object navigational calls that enable applications to perform any of the following on objects:

• Creating, accessing, locking, deleting, copying, and flushing objects

• Getting references to the objects

This class enables the type definer to specify when a class is capable of having persistent or transient instances. Instances of classes derived from PObject are either persistent or transient. A class (called "A") that is persistent-capable inherits from the PObject class:

class A : PObject { ... } 

The only methods valid on a NULL PObject are setName(), isNull(), and operator=().

Some of the methods provided, such as lock(), apply only for persistent instances, not for transient instances.

PObject()

PObject class constructor.

PObject();

PObject(
   const PObject &obj);

obj

flush()

This method flushes a modified persistent object to the database server.

void flush();

getConnection()

Returns the connection from which the persistent object was instantiated.

const Connection *getConnection() const;

getRef()

This method returns a reference to the persistent object.

RefAny getRef() const;

isLocked()

This method test whether the persistent object is locked. If the persistent object is locked, then TRUE is returned; otherwise, FALSE is returned.

bool isLocked() const;

isNull()

This method tests whether the persistent object is NULL. If the persistent object is NULL, then TRUE is returned; otherwise, FALSE is returned.

bool isNull() const;

lock()

Locks a persistent object on the database server.

void lock(
   PObject::LockOption lock_option);

lock_option

markDelete()

This method marks a persistent object as deleted.

void markDelete();

markModified()

This method marks a persistent object as modified or dirty.

void mark_Modified();

operator=()

This method assigns the value of a persistent object this PObject object. The nature (transient or persistent) of the object is maintained. NULL information is copied from the source instance.

PObject& operator=(
   const PObject& obj);

obj

operator delete()

Deletes a persistent or transient object. The delete operator on a persistent object removes the object from the application cache only. To delete the object from the database server, invoke the markDelete() method.

void operator delete(
   void *obj,
   size_t size);

obj

size

operator new()

This method is used to create a new object. A persistent object is created if the connection and table name are provided. Otherwise, a transient object is created.

void *operator new(
   size_t size);

void *operator new(
   size_t size,
   const Connection *conn,
   const string& tableName,
   const char *typeName);

void *operator new(
   size_t size,
   const Connection *conn,
   const string& tableName,
   const string& typeName,
   const string& schTableName="",
   const string& schTypeName="");

void *operator new(
   size_t size,
   const Connection *conn,
   const UString& tableName,
   const UString& typeName,
   const UString& schTableName="",
   const UString& schTypeName="");

size

conn

tableName

typeName

schTableName

schTypeName

pin()

This method pins the object and increments the pin count by one. As long as the object is pinned, it will not be freed by the cache even if there are no references to this object instance.

void pin();

setNull()

This method sets the object value to NULL.

void setNull();

unmark()

This method unmarks a persistent object as modified or deleted.

void unmark();

unpin()

This method unpins a persistent object. In the default mode, the pin count of the object is decremented by one. When this method is invoked with OCCI_PINCOUNT_RESET, the pin count of the object is reset. If the pin count is reset, this method invalidates all the references (Ref) pointing to this object. The cache sets the object eligible to be freed, if necessary, reclaiming memory.

void unpin(
   UnpinOption mode=OCCI_PINCOUNT_DECR);

mode