Message-ID: <gh-pgjdbc-pgjdbc-4119@github.com>
From: "davecramer (@davecramer)" <noreply+davecramer@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Sat, 30 May 2026 15:56:58 +0000
Subject: [pgjdbc/pgjdbc] PR #4119: refactor: replace literal chars with PgMessageType constants
List-Id: <gh-pgjdbc-pgjdbc.github.com>
X-GitHub-Additions: 12
X-GitHub-Author-Id: 406518
X-GitHub-Author-Login: davecramer
X-GitHub-Base: master
X-GitHub-Changed-Files: 2
X-GitHub-Commits: 1
X-GitHub-Deletions: 7
X-GitHub-Draft: true
X-GitHub-Head-Branch: fix_message_types
X-GitHub-Head-SHA: 9aaa849cb7b2ca28bd599eb80394ea21f0b6dc74
X-GitHub-Issue: 4119
X-GitHub-Merge-SHA: 71353529583b400d3f7c22dafa543d8ed0f35042
X-GitHub-Repo: pgjdbc/pgjdbc
X-GitHub-State: open
X-GitHub-Type: pull_request
X-GitHub-Url: https://github.com/pgjdbc/pgjdbc/pull/4119
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Replace raw character literals in QueryExecutorImpl with named constants from PgMessageType for readability and consistency:
- 'A', 'E', 'N' in notification polling and processResults
- 'I', 'T', 'E' transaction status in receiveRFQ

Add TRANSACTION_IDLE, TRANSACTION_OPEN, TRANSACTION_FAILED constants.

diff --git a/pgjdbc/src/main/java/org/postgresql/core/PgMessageType.java b/pgjdbc/src/main/java/org/postgresql/core/PgMessageType.java
index 3c2bfb76fb..2a6a37934c 100644
--- a/pgjdbc/src/main/java/org/postgresql/core/PgMessageType.java
+++ b/pgjdbc/src/main/java/org/postgresql/core/PgMessageType.java
@@ -58,4 +58,9 @@ public class PgMessageType {
   public static final byte COPY_DONE = 'c';
   public static final byte COPY_DATA = 'd';
 
+  // ReadyForQuery transaction status indicators
+  public static final byte TRANSACTION_IDLE = 'I';
+  public static final byte TRANSACTION_OPEN = 'T';
+  public static final byte TRANSACTION_FAILED = 'E';
+
 }
diff --git a/pgjdbc/src/main/java/org/postgresql/core/v3/QueryExecutorImpl.java b/pgjdbc/src/main/java/org/postgresql/core/v3/QueryExecutorImpl.java
index 304a55f9cc..9afb9a3788 100644
--- a/pgjdbc/src/main/java/org/postgresql/core/v3/QueryExecutorImpl.java
+++ b/pgjdbc/src/main/java/org/postgresql/core/v3/QueryExecutorImpl.java
@@ -935,14 +935,14 @@ public void processNotifies(int timeoutMillis) throws SQLException {
             setSocketTimeout(0); // Don't timeout after first char
           }
           switch (c) {
-            case 'A': // Asynchronous Notify
+            case PgMessageType.ASYNCHRONOUS_NOTICE:
               receiveAsyncNotify();
               timeoutMillis = -1;
               continue;
-            case 'E':
+            case PgMessageType.ERROR_RESPONSE:
               // Error Response (response to pretty much everything; backend then skips until Sync)
               throw receiveErrorResponse();
-            case 'N': // Notice Response (warnings / info)
+            case PgMessageType.NOTICE_RESPONSE: // warnings / info
               SQLWarning warning = receiveNoticeResponse();
               addWarning(warning);
               if (useTimeout) {
@@ -2372,7 +2372,7 @@ protected void processResults(ResultHandler handler, int flags, boolean adaptive
     while (!endQuery) {
       c = pgStream.receiveChar();
       switch (c) {
-        case 'A': // Asynchronous Notify
+        case PgMessageType.ASYNCHRONOUS_NOTICE:
           receiveAsyncNotify();
           break;
 
@@ -3002,15 +3002,15 @@ private void receiveRFQ() throws IOException {
 
     // Update connection state.
     switch (tStatus) {
-      case 'I':
+      case PgMessageType.TRANSACTION_IDLE:
         transactionFailCause = null;
         setTransactionState(TransactionState.IDLE);
         break;
-      case 'T':
+      case PgMessageType.TRANSACTION_OPEN:
         transactionFailCause = null;
         setTransactionState(TransactionState.OPEN);
         break;
-      case 'E':
+      case PgMessageType.TRANSACTION_FAILED:
         setTransactionState(TransactionState.FAILED);
         break;
       default: