Implementation comment. Now class view nodes hold the CsmXxx objects. When
parsing and reparsing headers, instances of these objects that correspond to the
same language element changes. While listening model events, ClassView gets
instances in notification and stores them.

Later on, when files are reparsed, new instances are created. But Class View
still holds old ones, which in turns holds CsmFile objects for containing files,
which in turn holds all declarations that are in fact already removed from
model, etc.  

Implementation Comment.
VV0: we can use weak references.
VV1: ClassView hold CsmXxx objects after handling model event. Objects are hold,
because they are in "added" set. But if they later replaced from model by new
ones, why we still hold them? Why they are not removed due to new model event by
analyzing "removed" set?
VV2: if objects remains in class view. Do we have doubled information about the
same declarations?

Weak references is better than usual ones, but we'd better not store references
to non-actual objects at all.

Changing CsmXxx objects with new ones when CsmChangeEvent reports change is
another solution.

But I think if we get rid of CsmXxx objects at all (probably except for projects
and namespaces), this will be the best solution. The reason is as follows.

Since our concept is that instances even for top-level objects aren't
persistent, we shouldn't store them on a long-term basis.

Fixed. Changes log is as follows.

Tag: cnd-nb50-dev
User: vkvashin
Date: 2006/07/20 07:04:10

Checking in classview/src/org/netbeans/modules/cnd/classview/model/EnumNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/EnumNode.java,v
 <--  EnumNode.java
new revision: 1.1.2.5; previous revision: 1.1.2.4
done
Checking in classview/src/org/netbeans/modules/cnd/classview/model/MemberNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/MemberNode.java,v
 <--  MemberNode.java
new revision: 1.1.2.5; previous revision: 1.1.2.4
done
Checking in
classview/src/org/netbeans/modules/cnd/classview/model/EnumeratorNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/EnumeratorNode.java,v
 <--  EnumeratorNode.java
new revision: 1.1.2.8; previous revision: 1.1.2.7
done
Checking in classview/src/org/netbeans/modules/cnd/classview/model/CVUtil.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/CVUtil.java,v
 <--  CVUtil.java
new revision: 1.1.2.4; previous revision: 1.1.2.3
done
Checking in
classview/src/org/netbeans/modules/cnd/classview/model/NamespaceNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/NamespaceNode.java,v
 <--  NamespaceNode.java
new revision: 1.1.2.6; previous revision: 1.1.2.5
done
Checking in classview/src/org/netbeans/modules/cnd/classview/model/LoadingNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/LoadingNode.java,v
 <--  LoadingNode.java
new revision: 1.1.2.3; previous revision: 1.1.2.2
done
Checking in classview/src/org/netbeans/modules/cnd/classview/model/ObjectNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/ObjectNode.java,v
 <--  ObjectNode.java
new revision: 1.1.2.7; previous revision: 1.1.2.6
done
Checking in classview/src/org/netbeans/modules/cnd/classview/model/ClassNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/ClassNode.java,v
 <--  ClassNode.java
new revision: 1.1.2.7; previous revision: 1.1.2.6
done
Checking in classview/src/org/netbeans/modules/cnd/classview/model/NPNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/NPNode.java,v
 <--  NPNode.java
new revision: 1.1.2.6; previous revision: 1.1.2.5
done
Checking in
classview/src/org/netbeans/modules/cnd/classview/model/GlobalVarNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/GlobalVarNode.java,v
 <--  GlobalVarNode.java
new revision: 1.1.2.4; previous revision: 1.1.2.3
done
Checking in
classview/src/org/netbeans/modules/cnd/classview/model/GlobalFuncNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/GlobalFuncNode.java,v
 <--  GlobalFuncNode.java
new revision: 1.1.2.4; previous revision: 1.1.2.3
done
Checking in classview/src/org/netbeans/modules/cnd/classview/model/TypedefNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/TypedefNode.java,v
 <--  TypedefNode.java
new revision: 1.1.2.5; previous revision: 1.1.2.4
done
Checking in classview/src/org/netbeans/modules/cnd/classview/model/BaseNode.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/model/Attic/BaseNode.java,v
 <--  BaseNode.java
new revision: 1.1.2.7; previous revision: 1.1.2.6
done
Checking in classview/src/org/netbeans/modules/cnd/classview/ClassView.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/Attic/ClassView.java,v
 <--  ClassView.java
new revision: 1.1.2.8; previous revision: 1.1.2.7
done
Checking in classview/src/org/netbeans/modules/cnd/classview/ClassViewModel.java;
/shared/data/ccvs/repository/cnd/classview/src/org/netbeans/modules/cnd/classview/Attic/ClassViewModel.java,v
 <--  ClassViewModel.java
new revision: 1.1.2.7; previous revision: 1.1.2.6
done
Checking in modelutil/src/org/netbeans/modules/cnd/modelutil/CsmNode.java;
/shared/data/ccvs/repository/cnd/modelutil/src/org/netbeans/modules/cnd/modelutil/Attic/CsmNode.java,v
 <--  CsmNode.java
new revision: 1.1.2.4; previous revision: 1.1.2.3
done