Message-ID: <gh-pgjdbc-pgjdbc-4073@github.com>
From: "davecramer (@davecramer)" <noreply+davecramer@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Fri, 15 May 2026 11:18:51 +0000
Subject: [pgjdbc/pgjdbc] PR #4073: Nio selector
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X-GitHub-Url: https://github.com/pgjdbc/pgjdbc/pull/4073
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Create connections using SocketChannel.open() instead of plain Socket
  when the default socket factory is used. This provides a Selector that
  can check socket readability without consuming data — enabling safe
  background notification polling in a future commit.
  
  - SocketChannel created in createSocket(), kept in blocking mode for
    normal I/O compatibility
  - Selector opened alongside the channel
  - isDataAvailable(timeoutMillis) uses selector.select() to check for
    incoming data without reading bytes — safe for background threads
  - hasSelector() indicates NIO availability
  - changeSocket() (SSL upgrade) invalidates channel/selector since SSL
    wraps the socket with a different stream
  - Selector closed in PGStream.close()
  
  Non-SSL connections get full Selector support. SSL connections fall back
  to the existing hasMessagePending() polling approach."