Message-ID: <gh-pgjdbc-pgjdbc-1325-c439541510@github.com>
From: "marschall (@marschall)" <noreply+marschall@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Fri, 16 Nov 2018 21:56:17 +0000
Subject: Re: [pgjdbc/pgjdbc] issue #1325: Additional jsr 310 support
In-Reply-To: <gh-pgjdbc-pgjdbc-1325@github.com>
References: <gh-pgjdbc-pgjdbc-1325@github.com>
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> I am not sure I agree. What I see is that LocalDateTime -> Timestamp conversion depends on the JVM default time zone.

It's the same with String -> Timestamp conversion which like LocalDateTime calls the deprecated constructor, see code below. To get from a date time / SQL TIMESTAMP to an instant / point in time / unix timestamp you need to have a time zone. For java.sql.Timestamp this is the JVM default time zone.

```java
String localDateTime = "2018-11-16 18:02:00";

TimeZone.setDefault(TimeZone.getTimeZone("America/Los_Angeles"));
Instant instant1 = Timestamp.valueOf(localDateTime).toInstant();
long epochMilli1 = instant1.toEpochMilli();

TimeZone.setDefault(TimeZone.getTimeZone("America/New_York"));
Instant instant2 = Timestamp.valueOf(localDateTime).toInstant();
long epochMilli2 = instant2.toEpochMilli();

System.out.printf("epochMilli1: %d%n", epochMilli1);
System.out.printf("epochMilli2: %d%n", epochMilli2);
System.out.println("same instant: " + instant1.equals(instant2));
```