Issue 3200: Container/member name clashes                                                                                                                                                                           (java2idl-rtf)
Source: International Business Machines (Mr. Simon C. Nash, nash@hursley.ibm.com)
Nature: Uncategorized Issue
Severity: 
Summary: There is a commonly occurring name collision that is not covered by the 
current name mangling rules.  This is demonstrated by the Java to IDL mapping
of java.util.Date.  The IDL generated gives a custom valuetype "Date" which 
contains an attribute "date", which is illegal in IDL.  This problem is not
unique to java.util.Date.

More generally, this collision occurs whenever a Java interface or class
being mapped to IDL contains a method or data member with the same name
as the interface or class (using a case-insensitive comparison).  For example,
the following Java definitions cause this problem:

Resolution: 
Revised Text: 
Actions taken:
January 9, 2000: received issue
May 16, 2006: closed issue
Discussion: 

End of Annotations:=====
Date: Sun, 09 Jan 2000 23:17:45 +0000
From: Simon Nash <nash@hursley.ibm.com>
Organization: IBM
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Subject: Container/member name clashes
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There is a commonly occurring name collision that is not covered by
the 
current name mangling rules.  This is demonstrated by the Java to IDL
mapping
of java.util.Date.  The IDL generated gives a custom valuetype "Date"
which 
contains an attribute "date", which is illegal in IDL.  This problem
is not
unique to java.util.Date.

More generally, this collision occurs whenever a Java interface or
class
being mapped to IDL contains a method or data member with the same
name
as the interface or class (using a case-insensitive comparison).  For
example,
the following Java definitions cause this problem:

public interface Foo extends java.rmi.Remote {
    public void foo() throws java.rmi.RemoteException;
}
public interface Foo extends java.rmi.Remote {
    public void Foo() throws java.rmi.RemoteException;
}
public class Bar implements java.io.Serializable {
    public int bar;
}
public class Bar implements java.io.Serializable {
    public int Bar;
}

It has been suggested that the rule in the section 1.3.2.7 may apply
to these 
cases.  This rule talks about IDL names that are defined in the same
IDL name 
scope.  However, in these cases, two different (but colliding) IDL
name scopes
are involved: the scope in which the container is defined, and the
scope within
the container.

If the 1.3.2.7 rule did apply, the first example above would be
treated as
follows:
 - the name of the IDL interface would be mangled to Foo_0
 - the name of the IDL operation would be mangled to foo_
This does not seem satisfactory because of the mangling of the
interface name.
Also, this fails to deal with the second example above, in which the
names do
not differ in case.  Therefore, the 1.3.2.7 rule should not apply and
a new 
mangling rule is required.

I propose that the following new section be added as 1.3.2.9, with the
existing
1.3.2.9 renumbered to 1.3.2.10.

1.3.2.9 Container names that clash with their members

In some cases, applying these rules for name mappings would generate
OMG IDL with
collisions between a container name and members of the container. This
is because
a Java member can have the same name as its container, but OMG IDL
members
cannot. The following rules are used to avoid such name collisions in
OMG IDL:
    Container names are mapped unchanged (subject to other mangling
rules).
    Java method, constant, or field names whose mapped name collides
with the mapped
  name of their Java container are mapped with an additional trailing
underscore.
For example, if a remote Java interface Foo has a method foo, the OMG
IDL interface
is called Foo and the OMG IDL operation is called foo_.

   Simon
-- 
Simon C Nash, Technology Architect, IBM Java Technology Centre
Tel. +44-1962-815156   Fax +44-1962-818999    Hursley, England
Internet: nash@hursley.ibm.com   Lotus Notes: Simon Nash@ibmgb