The contains(Object) and remove(Object) methods of Set implemented for
the Set<Map.Entry<String,String>> returned by the entrySet() method
of the Map<String,String> returned by ProcessBuilder.environment()
and implemented in the ProcessEnvironment.java files for Unix and Windows
have the following issues:

This code is currently accepted by Tiger's javac, but an imminent putback
will make this a compile error:

instanceof Map.Entry<String,String>

Further, these methods should throw the optional NullPointerException
and ClassCastExceptions as documented in Set.java.

A previous fix
 4932663 (process) Add more runtime error checking for environment map operation
ensured that these exceptions were thrown for other relevant methods, such
as ProcessEnvironment.environment().keySet().contains(Object)

This should be made consistent.

The following desirable property of Set is not satisfied by the set returned
by entrySet

For each element e of the Set s as returned by its iterator,
it should be true that
s.contains(e)

###@###.### 2004-04-05