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Message:

Collections framework: why not also containsNone

Posted by Steven Tolkin on April 24, 2000 at 5:39 PM

The Java 2 collections framework seems pretty well thought out.
But the interface does not have method containsNone.
These would permit certain relationships to be detected fast,
e.g. that sets are not disjoint.
For example s1.containsNone(s2) will return false as soon as one
common element is detected, showing they are not disjoint.

I do not think there is a way for me to extend the
interface in a way that will have this high performance property
because I do not have access to the implementation.
This must be done by Javasoft (or others writing their own
implementation, e.g. the Gnu http://www.classpath.org project).