IModelObject interface (dbgmodel.h)
The IModelObject interface encapsulates the notion of an object -- whether that object is an integer, a string, some complex type in the target address space of the debugger.
Inheritance
IModelObject inherits from IUnknown.
Methods
The IModelObject interface has these methods.
| IModelObject::AddParentModel The AddParentModel method adds a new parent model to the given object. |
| IModelObject::AddRef The AddRef method increments the reference count for an interface on an object. This method belongs to the IModelObject interface. |
| IModelObject::ClearConcepts The ClearConcepts method will remove all concepts from the instance of the object specified by this. |
| IModelObject::ClearKeys The ClearKeys method removes all keys and their associated values and metadata from the instance of the object specified by this. |
| IModelObject::Compare The Compare method compares two model objects and returns an indication of how those objects relate. |
| IModelObject::Dereference The Dereference method dereferences an object. |
| IModelObject::EnumerateKeyReferences The EnumerateKeyReferences method behaves similar to the EnumerateKeyValues method excepting that it returns references to the keys it enumerates instead of the value of the key. |
| IModelObject::EnumerateKeys Enumerates the keys within the dynamic key provider. |
| IModelObject::EnumerateKeyValues The EnumerateKeyValues method is the first method a client will turn to in order to enumerate all of the keys on an object. |
| IModelObject::EnumerateRawReferences The EnumerateRawReferences method enumerates references to all native children (fields, base classes, etc...) of the given object. |
| IModelObject::EnumerateRawValues The EnumerateRawValues method enumerates all native children (fields, base classes, etc...) of the given object. |
| IModelObject::GetConcept The GetConcept method will search for a concept on the object (or its parent model chain) and return an interface pointer to the concept interface. |
| IModelObject::GetContext The GetContext method returns the host context that is associated with the object. |
| IModelObject::GetContextForDataModel The GetContextForDataModel method is used to retrieve context information which was set up with a prior call to SetContextForDataModel. |
| IModelObject::GetIntrinsicValue The GetIntrinsicValue method returns the thing which is boxed inside an IModelObject. |
| IModelObject::GetIntrinsicValueAs The GetIntrinsicValueAs method behaves much as the GetIntrinsicValue method excepting that it converts the value to the specified variant type. |
| IModelObject::GetKey The GetKey method will get the value of (and the metadata associated with) a given key by name. |
| IModelObject::GetKeyReference If the object or one of its parent models has a key named according to the argument 'key', this will return a reference to that key. |
| IModelObject::GetKeyValue The GetKeyValue method is the first method a client will turn to in order to get the value of (and the metadata associated with) a given key by name. |
| IModelObject::GetKind The GetKind method returns what kind of object is boxed inside the IModelObject. |
| IModelObject::GetLocation The GetLocation method will return the location of the native object. While such a location is typically a virtual address within the address space of the debug target, it is not necessarily so. |
| IModelObject::GetNumberOfParentModels The GetNumberOfParentModels method returns the number of parent models which are attached to the given object instance. |
| IModelObject::GetParentModel The GetParentModel method returns the i-th parent model in the parent model chain of the given object. |
| IModelObject::GetRawReference The GetRawReference method finds a native construct within the given object and returns a reference to it. |
| IModelObject::GetRawValue The GetRawValue method finds a native construct within the given object. Such a construct may be a field, a base class, a field in a base class, a member function, etc. |
| IModelObject::GetTargetInfo The GetTargetInfo method is effectively a combination of the GetLocation and GetTypeInfo methods returning both the abstract location as well as native type of the given object. |
| IModelObject::GetTypeInfo The GetTypeInfo method will return the native type of the given object. If the object does not have native type information associated with it the call will still succeed but will return null. |
| IModelObject::IsEqualTo The IsEqualTo method compares a host context to another host context. If the two contexts are equivalent, an indication of this is returned. Note that this comparison is not interface equivalence. |
| IModelObject::QueryInterface The IModelObject::QueryInterface method retrieves pointers to the supported interfaces on an object. |
| IModelObject::Release The IModelObject::Release method decrements the reference count for an interface on an object. |
| IModelObject::RemoveParentModel The RemoveParentModel will remove a specified parent model from the parent search chain of the given object. |
| IModelObject::SetConcept The SetConcept method will place a specified concept on the object instance specified by the this pointer. |
| IModelObject::SetContextForDataModel The SetContextForDataModel method is used by the implementation of a data model to place implementation data on instance objects. |
| IModelObject::SetKey The SetKey method is the method a client will turn to in order to create a key on an object (and potentially associate metadata with the created key). |
| IModelObject::SetKeyValue The SetKeyValue method is the first method a client will turn to in order to set the value of a key. This method cannot be used to create a new key on an object. |
| IModelObject::TryCastToRuntimeType The TryCastToRuntimeType method will ask the debug host to perform an analysis and determine the actual runtime type (most derived class) of the given object. |
Remarks
One of the most basic yet powerful things about the data model is that it standardizes the definition of what an object is and how one interacts with an object. The IModelObject interface encapsulates the notion of an object -- whether that object is an integer, a floating point value, a string, some complex type in the target address space of the debugger, or some debugger concept like the notion of a process or a module.
There are several different things that can be held in (or boxed into) an IModelObject:
• Intrinsic Values - An IModelObject can be a container for a number of basic types: 8, 16, 32, or 64 bit signed or unsigned integers, booleans, strings, errors, or the notion of empty.
• Native Objects - An IModelObject can represent a complex type (as defined by the debugger's type system) within the address space of whatever the debugger is targeting
• Synthetic Objects - An IModelObject can be a dynamic object -- a dictionary if you will: a collection of key / value / metadata tuples and a set of concepts which define behaviors that aren't simply represented by key / value pairs.
• Properties - An IModelObject can represent a property: something whose value can be retrieved or altered with a method call. A property within an IModelObject is effectively an IModelPropertyAccessor interface boxed into an IModelObject
• Methods - An IModelObject can represent a method: something you can call with a set of arguments and get a return value. A method within an IModelObject is effectively an IModelMethod interface boxed into an IModelObject
An IModelObject is not an object in isolation. In addition to representing one of the types of objects shown above, each object has the notion of a chain of parent data models. This chain behaves much like a | JavaScript prototype chain. Instead of a linear chain of prototypes like JavaScript has, each data model object defines a linear chain of parent models. Each of those parent models in turn has another linear chain of its own set of parents. In essence, each object is an aggregation of the capabilities (properties, etc...) of both itself and every object in this tree. When a specific property is queried, if the object it is queried on does not support that property, the query is passed in linear order to each parent in turn. This creates a behavior where the search for a property is resolved by a depth-first search of the aggregate tree.
Extensibility within this object model is very simple given this notion that every object is an aggregate of itself and the tree of parent models. An extension can come in and add itself into the list of parent models for another object. Doing this extends the object. In this manner, it is possible to add capabilities onto anything: a particular instance of an object or value, a native type, the debugger's concept of what a process or thread is, or even the notion of "all iterable objects".
Requirements
| Requirement | Value |
|---|---|
| Header | dbgmodel.h |