10.4.4 Container Interface

The base interface Container is used to form a containment hierarchy in the Interface Repository. A Container can contain any number of objects derived from the Contained interface. All Containers, except for Repository, are also derived from Contained.

module CORBA {
   typedef sequence <Contained> ContainedSeq;
   interface Container : IRObject {
      Contained lookup (in ScopedName search_name);

      ContainedSeq contents (
          in DefinitionKind         limit_type,
          in boolean                exclude_inherited
          );
      ContainedSeq lookup_name (
          in Identifier             search_name,
          in long                   levels_to_search,
          in DefinitionKind         limit_type,
          in boolean                exclude_inherited
          );
  struct Description {
      Contained                     contained_object;
      DefinitionKind                kind;
      any                           value;
      };
      typedef sequence<Description> DescriptionSeq;
   DescriptionSeq describe_contents (
          in DefinitionKind         limit_type,
          in boolean                exclude_inherited,
          in long                   max_returned_objs
            );
      };
};

The lookup operation locates a definition relative to this container, given a scoped name using the OMG IDL rules for name scoping. An absolute scoped name (beginning double colons (::)) locates the definition relative to the enclosing Repository. If no object is found, a nil object reference is returned.

The contents operation returns the list of objects directly contained by or inherited into the object. The operation is used to navigate through the hierarchy of objects. Starting with the Repository object, a client uses this operation to list all of the objects contained by the Repository, all of the objects contained by the modules within the Repository, all of the interfaces and value types within a specific module, and so on.

limit_type

If limit_type is set to dk_all, objects of all types are returned. For example, if this is an InterfaceDef, the attribute, operation, and exception objects are all returned. If limit_type is set to a specific interface, only objects of that type are returned. For example, only attribute objects are returned if limit_type is set to dk_Attribute.

exclude_inherited

If set to TRUE, inherited objects (if there are any) are not returned. If set to FALSE, all contained objects (whether contained due to inheritance or because they were defined within the object) are returned.

The lookup_name operation is used to locate an object by name within a particular object or within the objects contained by that object. The describe_contents operation combines the contents operation and the describe operation. For each object returned by the contents operation, the description of the object is returned (that is, the object’s describe operation is invoked and the results are returned).

The lookup_name operation is used to locate an object by name within a particular object or within the objects contained by that object.

search_name

Specifies which name is to be searched for.

levels_to_search

Controls whether the lookup is constrained to the object the operation is invoked on, or whether the lookup should search through objects contained by the object as well. Setting levels_to_search to -1 searches the current object and all contained objects. Setting levels_to_search to 1 searches only the current object. Use of values of levels_to_search of 0 or of negative numbers other than -1 is undefined.

The describe_contents operation combines the contents operation and the describe operation. For each object returned by the contents operation, the description of the object is returned (i.e., the object’s describe operation is invoked and the results returned).

max_returned_objs

Limits the number of objects that can be returned in an invocation of the call to the number provided. Setting the parameter to -1 indicates return all contained objects.