#include <coherence/lang/TypedHolder.hpp>
Inherited by SubscriptHolder.
TypedHolder can safely be used in place of View but adds the ability to attempt a safe down cast to a Handle. This differs from a const_cast in that the down cast will only succeed if the TypedHolder had been assigned from a Handle, an assignment from a View results in a TypedHolder whose down cast operation will fail with a ClassCastException.
TypedHolder is not for general use, instead it is a convenience handle type which can be used for container like classes, which need to be able to contain both Handles and Views.
As with TypedHandles, TypedHolders are not thread-safe, and should not be used in a multi-threaded context even if protected by external synchronization. They should only be used as local variables. The most common place where thread-safe holders are needed is for object data members. For these cases the Coherence API includes a thread-safe variant MemberHolder.
Public Types | |
| typedef const T | ValueType |
| The type of the values the holder can reference. | |
| typedef T::Handle | ValueHandle |
| The Handle type for the referenced Object. | |
| typedef T::View | ValueView |
| The View type for the referenced Object. | |
Public Member Functions | |
| TypedHolder () | |
| Construct a new TypedHolder referencing NULL via a handle. | |
| TypedHolder (const TypedHolder &that) | |
| Construct a new TypedHolder referencing the same Object (and in the same manner) as the specified TypedHolder. | |
| template<class DT> | |
| TypedHolder (const TypedHandle< DT > &that) | |
| Construct a new TypedHolder referencing specified Object via a Handle or View. | |
| template<class DT> | |
| TypedHolder (const TypedHolder< DT > &that) | |
| Construct a new TypedHolder referencing the same Object (and in the same manner) as the specified TypedHolder. | |
| TypedHolder (T *po) | |
| Construct a new TypedHolder referencing the supplied object. | |
| template<class DT> | |
| TypedHolder (DT *po) | |
| Construct a new TypedHolder referencing the supplied object. | |
| ~TypedHolder () | |
| Destroy the TypedHolder. | |
| TypedHolder & | operator= (const TypedHolder &that) |
| Assign this TypedHolder to reference the same Object (and in the same manner) as the specified TypedHolder. | |
| template<class DT> | |
| TypedHolder & | operator= (const TypedHolder< DT > &that) |
| Assign this TypedHolder to reference the same Object (and in the same manner) as the specified TypedHolder. | |
| template<class PT> | |
| o () const | |
| Return a View to the referenced Object. | |
| const T & | operator * () const |
Dereference this holder, returning T&. | |
| const T * | operator-> () const |
| Dereference the TypedHolder. | |
Protected Member Functions | |
| bool | isHandle () const |
| Return true if the holder contains a handle. | |
| TypedHandle< T > | getHandle () const |
| Return a Handle to the referenced Object. | |
| void | set (const T *cp, bool fView, const ChainedHandleElement &that) |
| Set the Holder to reference an Object via a Handle. | |
| void | performAction (Action nAction) |
| Perform the specified action. | |
| void | safeDestruct (Action nAction) |
| Destruct the handle. | |
Protected Attributes | |
| const T * | m_cpo |
| The referenced Object. | |
| TypedHolder | ( | const TypedHolder< T > & | that | ) | [inline] |
Construct a new TypedHolder referencing the same Object (and in the same manner) as the specified TypedHolder.
| that | the TypedHolder to initialize from |
| TypedHolder | ( | const TypedHandle< DT > & | that | ) | [inline] |
Construct a new TypedHolder referencing specified Object via a Handle or View.
As a Handle is used, the TypedHolder can be used with the cast<...Handle>() method to retrieve the Handle from the Holder.
| that | a Handle or View to the Object to reference |
| TypedHolder | ( | const TypedHolder< DT > & | that | ) | [inline] |
Construct a new TypedHolder referencing the same Object (and in the same manner) as the specified TypedHolder.
| that | the TypedHolder to initialize from |
| TypedHolder | ( | T * | po | ) | [inline] |
Construct a new TypedHolder referencing the supplied object.
This method is primarily intended to support assignment from NULL, though it will work with other pointers.
| po | pointer to the Object to reference |
| TypedHolder | ( | DT * | po | ) | [inline] |
Construct a new TypedHolder referencing the supplied object.
| po | pointer to the Object to reference |
| TypedHolder& operator= | ( | const TypedHolder< T > & | that | ) | [inline] |
Assign this TypedHolder to reference the same Object (and in the same manner) as the specified TypedHolder.
| that | the TypedHolder to assign from |
| TypedHolder& operator= | ( | const TypedHolder< DT > & | that | ) | [inline] |
Assign this TypedHolder to reference the same Object (and in the same manner) as the specified TypedHolder.
| that | the TypedHolder to assign from |
| o | ( | ) | const [inline] |
| const T& operator * | ( | ) | const [inline] |
Dereference this holder, returning T&.
T& reference to the referenced Object| NullPointerException | if the this holder is NULL |
| const T* operator-> | ( | ) | const [inline] |
| bool isHandle | ( | ) | const [inline, protected] |
Return true if the holder contains a handle.
| TypedHandle<T> getHandle | ( | ) | const [inline, protected] |
| void set | ( | const T * | cp, | |
| bool | fView, | |||
| const ChainedHandleElement & | that | |||
| ) | [inline, protected] |
| void performAction | ( | Action | nAction | ) | [inline, protected] |
Perform the specified action.
| nAction | the action to perform |
| void safeDestruct | ( | Action | nAction | ) | [inline, protected] |
Destruct the handle.
Any exception occurring during distribution will simply be printed, the intent of this function is for use during TypedHandle destruction. It is not the common path and is pulled out to encourage inlining of the destructor.