8384062: Add a new method List::removeAtIndex to avoid overload confusion

[minborg]

This PR proposes to add a new default method List::removeAtIndex.

There are two overloads of the method List::remove, and if the list is of type List<Integer>, the overload resolution could pick a surprising variant.

Hence, it is better to add a separate method that removes an element based on its index.

It is proposed that the E remove(int index) method is not @Deprecated. Instead, we add verbiage to promote the new method over the old one.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Change requires CSR request JDK-8384074 to be approved
• Commit message must refer to an issue

Issues

• JDK-8384062: Add a new method List::removeAtIndex to avoid overload confusion (Enhancement - P4)
• JDK-8384074: Add a new method List::removeAtIndex to avoid overload confusion (CSR)

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[bridgekeeper]

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[openjdk]

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[openjdk]

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[minborg]

/csr

[openjdk]

@minborg has indicated that a compatibility and specification (CSR) request is needed for this pull request.

@minborg please create a CSR request for issue JDK-8384062 with the correct fix version. This pull request cannot be integrated until the CSR request is approved.

[mlbridge]

Webrevs

• 00: Full (d5fa4ee4)

[mlbridge]

Mailing list message from Remi Forax on core-libs-dev:

Hello,
the problem with java.util.List (unlike say Runtime.Version or Optional#get) is that List is *both* used directly and implemented.

For users, it is clear that removeAtIndex() should be used.

For implementors of java.util.List, it is not clear how to guarantee that remove(index) and removeAtIndex() are always in sync,
especially because most of the named implementation of java.util.List can be inherited.

We do not want to be in a situation where remove(index) and removeAtIndex() have two different implementations.

So I think it's premature to create a PR until we discuss what can be done/should be done to solve that problem.

Should we changed the tooling (javac, IDEs?) so implementation drift are recognized and reported ?
Are there other solutions ?

regards,
Rémi

----- Original Message -----

From: "Per Minborg" <pminborg@openjdk.org>
To: "core-libs-dev" <core-libs-dev@openjdk.org>
Sent: Thursday, May 7, 2026 10:19:39 AM
Subject: RFR: 8384062: Add a new method List::removeAtIndex to avoid overload confusion