8376031: HttpsURLConnection.getServerCertificates() throws "java.lang.IllegalStateException: connection not yet open" for the HEAD method

[rm-gh-8]

Backporting JDK-8376031: HttpsURLConnection.getServerCertificates() throws "java.lang.IllegalStateException: connection not yet open" for the HEAD method.

This PR fixes HttpsURLConnection.getServerCertificates() throwing IllegalStateException after calling getResponseCode() on no-body responses by preserving the SSL session when HttpURLConnection automatically disconnects (sets http = null, connected = false) before returning the empty body stream, allowing SSL information extraction until explicit disconnect() is called.

The PR contains a modified commit that defines RSPBODY_EMPTY as a local constant rather than using a static import in the GetServerCertificates.java test, since the static import depends on JDK-8331195, which requires CSR approval before backporting.

For parity with Oracle JDK.

Ran related tests on linux-x64, linux-aarch64, macos-aarch64 and windows-x64:

make test TEST=test/jdk/sun/net/www/protocol/https/HttpsURLConnection/GetServerCertificates.java

Results attached:

windows-x64-specific-test.log
macos-aarch64-specific-test.log
linux-x64-specific-test.log
linux-aarch64-specific-test.log

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8376031 needs maintainer approval

Integration blocker

 ⚠️ Dependency #348 must be integrated first

Issue

• JDK-8376031: HttpsURLConnection.getServerCertificates() throws "java.lang.IllegalStateException: connection not yet open" for the HEAD method (Bug - P3 - Approved)

Reviewers

• Paul Hohensee (@phohensee - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/349/head:pull/349
$ git checkout pull/349

Update a local copy of the PR:
$ git checkout pull/349
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/349/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 349

View PR using the GUI difftool:
$ git pr show -t 349

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/349.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back rm-gh-8! A progress list of the required criteria for merging this PR into pr/348 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[mlbridge]

Webrevs

• 02: Full - Incremental (e6d71e87)
• 01: Full - Incremental (13ff03bc)
• 00: Full (24a9165b)

[phohensee]

Please add the import of RSPBODY_EMPTY, but comment it out and add a reference to 8331195.

[phohensee]

Thanks, good.

[rm-gh-8]

/approval request for backport of JDK-8376031: HttpsURLConnection.getServerCertificates() throws "java.lang.IllegalStateException: connection not yet open" for the HEAD method.

This PR fixes HttpsURLConnection.getServerCertificates() throwing IllegalStateException after calling getResponseCode() on no-body responses by preserving the SSL session when HttpURLConnection automatically disconnects (sets http = null, connected = false) before returning the empty body stream, allowing SSL information extraction until explicit disconnect() is called.

The PR contains a modified commit that defines RSPBODY_EMPTY as a local constant rather than using a static import in the GetServerCertificates.java test, since the static import depends on JDK-8331195, which requires CSR approval before backporting.

For parity with Oracle JDK.

Low risk - the change preserves existing behavior for normal responses while fixing the edge case of empty-body responses; the saved session is properly cleared on reconnection/disconnect to prevent stale data; comprehensive test coverage validates HEAD, 204, 304, and no-body 200 responses; refactoring consolidates session access logic without changing the public API contract.

[openjdk]

@rm-gh-8
8376031: The approval request has been created successfully.