Message-ID: <gh-pgjdbc-pgjdbc-3887@github.com>
From: "m-van-tilburg (@m-van-tilburg)" <noreply+m-van-tilburg@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Thu, 04 Dec 2025 14:22:17 +0000
Subject: [pgjdbc/pgjdbc] PR #3887: fix: make all Calendar instances proleptic Gregorian (#3837)
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X-GitHub-Issue: 3887
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Calendar instances created with Calendar.getInstance() or new GregorianCalendar() are by default a hybrid of the Julian and the Gregorian calendar. Java classes like java.sql.Date and SimpleDateFormat also (sometimes) use Calendar instances and therefore might also be affected. This differs from the java.time classes that use the proleptic Gregorian calendar by default. The postgresql server also uses the proleptic Gregorian calendar and therefore it makes sense to make all Calendar instances in the pgjdbc code proleptic Gregorian too. This will fix #3837