From 7ee339a754e22117459713802d4ba595dbf547b2 Mon Sep 17 00:00:00 2001
From: kimminseok <alstjr706@naver.com>
Date: Sun, 26 Oct 2025 22:09:47 +0900
Subject: [PATCH] Extract timezone offset calculation to helper method

---
 .../java/tech/turso/jdbc4/JDBC4ResultSet.java | 36 +++++--------------
 1 file changed, 9 insertions(+), 27 deletions(-)

diff --git a/bindings/java/src/main/java/tech/turso/jdbc4/JDBC4ResultSet.java b/bindings/java/src/main/java/tech/turso/jdbc4/JDBC4ResultSet.java
index d106fdd7e..b10e28be5 100644
--- a/bindings/java/src/main/java/tech/turso/jdbc4/JDBC4ResultSet.java
+++ b/bindings/java/src/main/java/tech/turso/jdbc4/JDBC4ResultSet.java
@@ -838,15 +838,7 @@ public final class JDBC4ResultSet implements ResultSet, ResultSetMetaData {
     if (date == null || cal == null) {
       return date;
     }
-
-    final Calendar localCal = Calendar.getInstance();
-    localCal.setTime(date);
-
-    final long offset =
-        cal.getTimeZone().getOffset(date.getTime())
-            - localCal.getTimeZone().getOffset(date.getTime());
-
-    return new Date(date.getTime() + offset);
+    return new Date(date.getTime() + calculateTimezoneOffset(date.getTime(), cal));
   }
 
   @Override
@@ -862,15 +854,7 @@ public final class JDBC4ResultSet implements ResultSet, ResultSetMetaData {
     if (time == null || cal == null) {
       return time;
     }
-
-    final Calendar localCal = Calendar.getInstance();
-    localCal.setTime(time);
-
-    final long offset =
-        cal.getTimeZone().getOffset(time.getTime())
-            - localCal.getTimeZone().getOffset(time.getTime());
-
-    return new Time(time.getTime() + offset);
+    return new Time(time.getTime() + calculateTimezoneOffset(time.getTime(), cal));
   }
 
   @Override
@@ -886,15 +870,7 @@ public final class JDBC4ResultSet implements ResultSet, ResultSetMetaData {
     if (timestamp == null || cal == null) {
       return timestamp;
     }
-
-    final Calendar localCal = Calendar.getInstance();
-    localCal.setTime(timestamp);
-
-    final long offset =
-        cal.getTimeZone().getOffset(timestamp.getTime())
-            - localCal.getTimeZone().getOffset(timestamp.getTime());
-
-    return new Timestamp(timestamp.getTime() + offset);
+    return new Timestamp(timestamp.getTime() + calculateTimezoneOffset(timestamp.getTime(), cal));
   }
 
   @Override
@@ -1342,6 +1318,12 @@ public final class JDBC4ResultSet implements ResultSet, ResultSetMetaData {
     throw new UnsupportedOperationException("not implemented");
   }
 
+  private long calculateTimezoneOffset(long timeMillis, Calendar targetCal) {
+    Calendar localCal = Calendar.getInstance();
+    return targetCal.getTimeZone().getOffset(timeMillis)
+        - localCal.getTimeZone().getOffset(timeMillis);
+  }
+
   @FunctionalInterface
   public interface ResultSetSupplier<T> {
     T get() throws Exception;