### Summary This patch addresses the issue where `HttpResponse.body()` returns `null` for 407 responses when using HTTPS through a proxy, while HTTP requests correctly return the response body.
### Problem When an HTTPS request receives a 407 Proxy Authentication Required response, the response body is discarded during CONNECT tunnel establishment. This is inconsistent with HTTP behavior where the body is properly returned. **Root cause:** - HTTPS uses `MultiExchange<Void>` for CONNECT requests - The body is explicitly ignored via `ignoreBody()` on 407 responses - No mechanism exists to preserve the body for later retrieval ### Proposed Solution I propose the following changes to preserve and return the 407 response body: 1. **PlainTunnelingConnection.java**: Change `MultiExchange<Void>` to `MultiExchange<byte[]>` and read the body on 407 responses instead of ignoring it 2. **ProxyAuthenticationRequired.java**: Add `proxyResponseBody` field to carry the body bytes through the exception 3. **Exchange.java**: Cache both the proxy response and body, then return them when the application calls `body()` ### Testing Added comprehensive test (`ProxyAuthHttpTest.java`) covering: - Basic HTTP and HTTPS 407 responses - Multiple `BodyHandler` types: `ofString()`, `ofByteArray()`, `ofInputStream()`, `ofLines()` - Response headers validation **Test results**: 38/38 passed ### Notes - This change only affects 407 responses; all other flows remain unchanged - The cached body is cleared after first use to prevent reuse - No changes to public APIs; internal implementation only I'd appreciate any feedback on this approach. If there's a better way to handle this, I'm happy to revise. ------------- Commit messages: - 8328894: Add test for 407 response body with various handlers - 8328894: Cache and return 407 response body to application - 8328894: Add proxyResponseBody field to preserve 407 body - 8328894: Read 407 response body in HTTPS CONNECT tunneling Changes: https://git.openjdk.org/jdk/pull/28232/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28232&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8357554 Stats: 372 lines in 4 files changed: 301 ins; 8 del; 63 mod Patch: https://git.openjdk.org/jdk/pull/28232.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/28232/head:pull/28232 PR: https://git.openjdk.org/jdk/pull/28232
