#include <coherence/lang/TypedHandle.hpp>
Inherited by BoxHandle, Immutable, String::StringHandle, SubscriptHandle, and throwable_spec::hierarchy.
Managed objects manage their own life cycle, rather the relying on user code to identify when they should be deleted. The TypedHandle class can be used with any class implementing the coherence::lang::Object interface.
By convention each Object implementation will include two typedefs for TypedHandle to make their usage easier. For instance the class "Foo" would define Foo::Handle as a TypedHandle<Foo>. The second typedef is called a View, and is analogous to a pointer to a const, that is Foo::View is TypedHandle<const Foo>.
TypedHandles 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 handles are needed is for object data members. For these cases the Coherence API includes thread-safe handles/views, namely MemberHandle/View and WeakHandle/View.
Public Types | |
| typedef T | ValueType |
| A concrete object type that is referenced by this handle. | |
|
typedef value_less_functor < T > | value_compare |
| Functor allowing handles to be used within STL sorted containers, such as std::map and std::set, and to have their equivalence checks delegated to the Objects they reference. | |
|
typedef value_equal_functor < T > | value_equal |
| Functor allowing handles to be used within hash containers, such as the SGI and MS style hash_map and hash_set, and to have their equivalence checks delegated to the Objects they reference. | |
|
typedef value_hash_functor < T > | value_hasher |
| Functor allowing handles to be used within hash containers, such as the SGI as MS style hash_map and hash_set, and to have their hash computation be based on the value of the referenced Object. | |
| typedef identity_hash_functor < T > | identity_hasher |
| Functor allowing handles to be used within hash containers, such as the SGI as MS style hash_map and hash_set, and to have their hash computation be based on their identity, i.e. | |
Public Member Functions | |
| T () | |
| Construct a handle that references NULL. | |
| T (T *po) | |
| Construct a handle that references given Object. | |
| T (T *po, const ChainedHandleElement &that) | |
| Construct a handle which is linked to another chained element type. | |
| template<class DT> | |
| T (const TypedHandle< DT > &that) | |
| Construct a handle from a handle to a derived type. | |
| T (const TypedHandle< T > &that) | |
| Construct a handle from another handle. | |
| ~ () | |
| Destruct this handle. | |
| T & | operator * () const |
Dereference this handle, returning T&. | |
| T * | operator-> () const |
Dereference this handle, returning T*. | |
| TypedHandle< T > & | operator= (const TypedHandle< T > &h) |
| Assign this TypedHandle another Object to reference. | |
| template<class DT> | |
| TypedHandle< T > & | operator= (const TypedHandle< DT > &h) |
| Assign this TypedHandle from a handle to a derived type. | |
| template<class AT> | |
| bool | operator< (const TypedHandle< AT > &h) const |
| Compare two handles with "less-than" predicate. | |
Protected Member Functions | |
| T * | get () const |
| Return pointer without null checking. | |
| void | set (T *o, const ChainedHandleElement &that) |
| Set the TypedHandle to attach to the supplied pointer. | |
| void | performAction (Action nAction) |
| Perform the specified action. | |
Protected Attributes | |
| T * | m_o |
| Pointer to the referenced object. | |
Classes | |
| class | identity_hash_functor |
| Identity based hash functor which is compatible with both the SGI and MS style hash containers. More... | |
| class | value_equal_functor |
| The binary functor that compares values pointed by the handles for equality. More... | |
| class | value_hash_functor |
| Value based hash functor which is compatible with both the SGI and MS style hash containers. More... | |
| class | value_less_functor |
| The binary functor that compares objects pointed by the handles with the "less-than" operator. More... | |
| typedef identity_hash_functor<T> identity_hasher |
Functor allowing handles to be used within hash containers, such as the SGI as MS style hash_map and hash_set, and to have their hash computation be based on their identity, i.e.
the reference they contain.
| T | ( | T * | po | ) | [inline] |
| T | ( | T * | po, | |
| const ChainedHandleElement & | that | |||
| ) | [inline] |
Construct a handle which is linked to another chained element type.
This is used for chaining Holders to Handles.
| po | the pointer to assign from | |
| that | the "owner" of that pointer |
| T | ( | const TypedHandle< DT > & | that | ) | [inline] |
Construct a handle from a handle to a derived type.
New handle will reference the same Object that the given handle.
| that | another handle |
| T | ( | const TypedHandle< T > & | that | ) | [inline] |
Construct a handle from another handle.
New handle will reference the same Object that the given handle.
| that | another handle |
| T& operator * | ( | ) | const [inline] |
Dereference this handle, returning T&.
T& reference to the referenced Object| NullPointerException | if the this handle is NULL |
| T* operator-> | ( | ) | const [inline] |
Dereference this handle, returning T*.
T* pointer to the referenced Object| NullPointerException | if the this handle is NULL |
| bool operator< | ( | const TypedHandle< AT > & | h | ) | const [inline] |
Compare two handles with "less-than" predicate.
This is only an identity based comparison, and does not take the value into account.
| T* get | ( | ) | const [inline, protected] |
Return pointer without null checking.
Does NOT throw NullPointerException.
One should use h.get() to get raw T* pointer. Please do not use neither &*h (as it may throw NullPointerException) nor (T*)h (as it may perform unsafe unchecked type cast).
| void set | ( | T * | o, | |
| const ChainedHandleElement & | that | |||
| ) | [inline, protected] |
Set the TypedHandle to attach to the supplied pointer.
Any existing attachment will be detached.
| o | the address of the object to point to or NULL |
| void performAction | ( | Action | nAction | ) | [inline, protected] |
Perform the specified action.
| nAction | the action to perform |